UC-NRLF 


SDDCAIIOH  UBB; 


READER    IN    BOTANY 


L 

FROM    SEED  re    LEAF. 


SELECTED   AND  ADAPTED  FROM  WELL- 
KNOWN   AUTHORS, 

BY 

JANE    H.    NEWELL, 


BOSTON,  U.S.A. : 

GINN   &  COMPANY,    PUBLISHERS. 

I895. 


EDUCATION 


COPYRIGHT,  1889. 
Bv  JANE  H.   NEWELL. 


ALL  RIGHTS  RESERVED. 


TYPOGRAPHY  BY  J.  S.  GUSHING  &  Co.,  BOSTON,  U.S.A. 
PRESSWORK  BY  GINN  &  Co.,  BOSTON,  U.S.A. 


A)4- 


v.  l 

EDUC, 

PREFACE. 


THE  purpose  of  this  book  is  to  supply  a  course 
of  reading  calculated  to  awaken  the  interest  of  the 
pupil  in  the  study  of  the  life  and  habits  of  plants. 
It  is  not  to  be  judged  as  a  complete  work  in  itself, 
but  as  a  series  of  articles  bearing  on  the  subjects 
of  the  lessons  described  in  "  Outlines  of  Lessons  in 
Botany."  1 

Four  of  the  articles,  Nos.  II.,  III.,  XIII.,  and  XV., 
have  been  written  especially  for  this  Reader.  Three 
articles  are  translated  from  "  Pflanzenleben,"  2  and  two 
others  owe  much  of  their  matter  to  the  same  book, 
which  is  a  very  charming  popular  account  of  the  most 
recent  discoveries  in  the  physiology  of  plants.  The 
other  chapters  are  from  various  sources. 

Sachs'  "Lectures  on  the  Physiology  of  Plants"3  has 
supplied  several  interesting  notes,  and  is  an  invalu- 
able work  to  the  teacher  who  wishes  to  become  more 
acquainted  with  this  fascinating  new  field  of  study. 

1  "  Outlines  of  Lessons  in  Botany."     By  Jane  H.  Newell.     Boston  : 
Ginn  &  Co.     1889. 

2  "  Pflanzenleben."    By  Anton  Kerner  von  Marilaun.   Leipzig.    1888. 

3  "Lectures  on  the  Physiology  of  Plants."     By  Julius  von  Sachs. 
Translated  by  H.  Marshall  Ward.     Oxford,     1887. 


M75O3O3 


CONTENTS. 


PAGE 

I.    ORIGIN  OF  CULTIVATED  PLANTS 1 

Extracts  from  CHARLES  DARWIN   and  ALPH.  DE  CAN- 
DOLLE. 

II.    THE  COTTON  PLANT 12 

NINA  MOORE. 

III.  SEED-FOOD 24 

FREDERICK  LEROY  SARGENT. 

IV.  MOVEMENTS  OF  SEEDLINGS 34 

Extracts  from  CHARLES  DARWIN. 

V.    THE  BIRTH  OF  PICCIOLA 50 

From  the  French  of  JOSEPH  XAVIER  SAINTINE. 

VI.    ROOT    AND   CROWN.     Relative  Position  of  Leaves  and 

Rootlets 60 

From  the  German  of  A.  KERNKR  VON  MARILAUN.  "  Pflan- 
zenleben." 

VII.    TREES  IN  WINTER 72 

VIII.    YOUNG  AND  OLD  LEAVES     ........     84 

From  the  German.    "  Pflanzenleben.'; 

IX.    LEAF-ARRANGEMENT 96 

SIR   JOHN    LUBBOCK.      From    "Flowers,    Fruits,    and 
Leaves." 

X.    CLIMBING  PLANTS 115 

Extracts  from  CHARLES  DARWIN. 

XI.   PROTECTION   OF  THE   GREEN   TISSUE    FROM   THE 

ATTACKS  OF  ANIMALS 134 

From  the  German.    "  Pflanzenleben." 


vi  CONTENTS. 

PAGE 

XII.   TRANSPIRATION 149 

XIII.  USES  OF  FORESTS  AND  OTHER  PLANT  COVERING  OF 

THE  EARTH 160 

N.  S.  SHALER. 

XIV.  PARASITIC  PLANTS 172 

XV.    INSECTIVOROUS  PLANTS 187 

MARY  TREAT. 


A  READER  IN  BOTANY. 


ORIGIN    OF    CULTIVATED    PLANTS. 

ALL  our  food  comes  through  plants.  They  are 
the  link  between  the  animal  and  mineral  king- 
doms. They  are  able  to  take  from  the  earth  and 
the  air  the  inorganic  substances  they  require,  and 
to  build  them  into  organized  material  on  which 
animals  can  live.  Directly,  through  the  use  of 
the  plants  themselves,  and  indirectly,  through 
animals  which  have  been  nourished  by  plants,  we 
get  all  our  food  through  the  vegetable  kingdom. 

Many  of  our  fine  varieties  of  garden  vegetables 
and  flowers  have  been  produced  in  the  following 
way:  — 

The  gardener  sows  seed  of  his  best  plants,  and 
selects  from  the  offspring  those  which  best  show 
the  characters  he  wishes  to  increase.  From  the 
offspring  of  these  he  again  selects  the  best,  and  so 


2  ORIGIN    OF    CULTIVATED    PLANTS. 

on,  through  many  generations,  till  the  fine  color, 
or  sweet  taste,  or  great  size,  he  has  been  working 
towards,  becomes  perfected.  Then  these  improved 
plants  can  be  multiplied  by  grafts,  buds,  or  cuttings, 
which  usually  transmit  the  exact  qualities  of  the 
parent,  until  the  variety  is  well  established. 
The  seedlings  of  a  plant  have  a  tendency  to  inherit 
the  characteristics  of  the  parents,  and  also  to  vary 
somewhat.  By  selecting,  through  a  long  series  of 
generations,  individuals  tending  towards  a  certain 
desired  character,  and  allowing  the  less  desirable 
to  perish,  distinct  varieties  are  produced.  In  this, 
man  has  unconsciously  followed  the  process  of 
Nature  herself,  who  through  long  ages  has  been 
improving  her  work  by  suffering  her  weaker  and 
poorer  children  to  perish,  through  their  lack  of 
power  to  compete  with  those  better  suited  to  their 
surroundings.  The  latter  survive  and  hand  down 
their  qualities  to  their  offspring,  whose  descend- 
ants in  their  turn,  best  adapted  to  take  advantage 
of  their  opportunities,  usurp  the  room,  which  is 
not  wide  enough  for  all. 

With  animals  the  process  is  the  same.  The 
wonderful  speed  of  the  trotter,  the  pointing  of 
the  hunting-dog,  the  direct  flight  of  the  carrier- 
pigeon  towards  home,  are  all  instincts  that  have 


ORIGIN    OF    CULTIVATED    PLANTS.  6 

been   developed  by  man  by  the  same  process  of 
selection.     Darwin l  says  :  — 

"From  a  remote  period,  in  all  parts  of  the 
world,  man  has  subjected  many  animals  and  plants 
to  domestication  or  culture.  Man  has  no  power 
of  altering  the  absolute  conditions  of  life ;  he  can- 
not change  the  climate  of  any  country;  he  adds 
no  new  element  to  the  soil ;  but  he  can  remove  an 
animal  or  plant  from  one  climate  or  soil  to  an- 
other, and  give  it  food  on  which  it  did  not  subsist 
in  a  natural  state.  .  .  .  Although  man  does  not 
cause  variability  and  cannot  even  prevent  it,  he 
can  select,  preserve,  and  accumulate  the  variations 
given  to  him  by  the  hand  of  nature,  in  any  way 
that  he  chooses ;  and  thus  he  can  certainly  pro- 
duce a  great  result.  Selection  may  be  followed 
either  methodically  and  intentionally,  or  uncon- 
sciously and  unintentionally.  Man  may  select  and 
preserve  each  successive  variation  with  the  distinct 
intention  of  improving  and  altering  a  breed,  in 
accordance  with  a  preconceived  idea ;  and  by  thus 
adding  up  variations,  often  so  slight  as  to  be  im- 
perceptible to  an  uneducated  eye,  he  has  effected 
wonderful  changes  and  improvements.  It  can 

1  "  The  Variation  of  Animals  and  Plants  under  Domestication."  By 
Charles  Darwin.  New  York.  D.  Appleton  &  Co.  1887.  Vol.  I.  p.  2. 


4  ORIGIN    OF    CULTIVATED    PLANTS. 

also  be  clearly  shown  that  man,  without  any 
intention  or  thought  of  improving  the  breed,  by 
preserving  in  each  successive  generation  the  indi- 
viduals which  he  prizes  most,  and  by  destroying 
the  worthless  individuals,  slowly,  though  surely, 
induces  great  changes.  As  the  will  of  man  thus 
comes  into  play,  we  can  understand  how  it  is  that 
domesticated  breeds  show  adaptation  to  his  wants 
and  pleasures.  We  can  further  understand  how  it 
is  that  domestic  races  of  animals  and  cultivated 
races  of  plants  often  exhibit  an  abnormal  char- 
acter, as  compared  with  natural  species ;  for  they 
have  been  modified  not  for  their  own  benefit,  but 
for  that  of  man." 

Until  quite  lately,  the  origin  of  almost  all  cul- 
tivated plants  was  completely  unknown.  M.  Al- 
phonse  De  Candolle  investigated  the  subject  very 
thoroughly,  publishing  his  first  results  about  thirty 
years  ago.  In  a  recent  review  of  the  whole  sub- 
ject1 he  gives  a  list  of  two  hundred  and  forty- 
seven  species  of  cultivated  plants,  with  their  geo- 
graphical origins,  and  the  number  of  centuries  or 
thousands  of  years  during  which  each  has  been 
cultivated,  as  far  as  can  be  known.  He  says : 2 

1 "  Origin  of  Cultivated  Plants."  By  Alph.  De  Candolle.  New  York. 
1).  Appleton  &  Co.  1885.  2  page  i 


OKIGIN    OF    CULTIVATED    PLANTS.  0 

"  The  traditions  of  ancient  peoples,  embellished  by 
poets,  have  commonly  attributed  the  first  steps  in 
agriculture  and  the  introduction  of  useful  plants, 
to  some  divinity,  or  at  least  to  some  great  em- 
peror or  Inca.  Reflection  shows  that  this  is  hardly 
probable,  and  observation  of  the  attempts  at  agri- 
culture among  the  savage  tribes  of  our  own  day 
proves  that  the  facts  are  quite  otherwise. 

"  In  the  progress  of  civilization  the  beginnings 
are  usually  feeble,  obscure,  and  limited.  There  are 
reasons  why  this  should  be  the  case  with  the  first 
attempts  at  agriculture  or  horticulture.  Between 
the  custom  of  gathering  wild  fruits,  grain,  and 
roots,  and  that  of  the  regular  cultivation  of  the 
plants  which  produce  them,  there  are  several  steps. 
A  family  may  scatter  seeds  around  its  dwelling, 
and  provide  itself  the  next  year  with  the  same 
product  in  the  forest.  Certain  fruit  trees  may 
exist  near  a  dwelling  without  our  knowing  whether 
they  were  planted,  or  whether  the  hut  was  built 
beside  them  in  order  to  profit  by  them.  War  and 
the  chase  often  interrupt  attempts  at  cultivation. 
Rivalry  and  mistrust  cause  the  imitation  of  one 
tribe  by  another  to  make  but  slow  progress.  If 
some  great  personage  command  the  cultivation  of 
a  plant,  and  institute  some  ceremonial  to  show  its 


6  ORIGIN    OF    CULTIVATED    PLANTS. 

utility,  it  is  probably  because  obscure  and  unknown 
men  have  previously  spoken  of  it,  and  that  suc- 
cessful experiments  have  been  already  made.  A 
longer  or  shorter  succession  of  local  and  short- 
lived experiments  must  have  occurred  before  such 
a  display,  which  is  calculated  to  impress  an  already 
numerous  public.  It  is  easy  to  understand  that 
there  must  have  been  determining  causes  to  excite 
these  attempts,  to  renew  them,  to  make  them  suc- 
cessful. 

"  The  first  cause  is  that  such  or  such  a  plant, 
offering  some  of  those  advantages  which  all  men 
seek,  must  be  within  reach.  The  lowest  savages 
know  the  plants  of  their  country ;  but  the  exam- 
ple of  the  Australians  and  Patagonians  shows  that 
if  they  do  not  consider  them  productive  and  easy 
to  rear,  they  do  not  entertain  the  idea  of  cultivat- 
ing them.  Other  conditions  are  sufficiently  evi- 
dent :  a  not  too  rigorous  climate  ;  in  hot  countries, 
the  moderate  duration  of  drought ;  some  degree  of 
security  and  settlement ;  lastly,  a  pressing  neces- 
sity, due  to  insufficient  resources  in  fishing,  hunt- 
ing, or  in  the  production  of  indigenous  and  nutri- 
tious plants,  such  as  the  chestnut,  the  date-palm, 
the  banana,  or  the  bread-fruit  tree.  When  men 
can  live  without  work,  it  is  what  they  like  best. 


ORIGIN    OF    CULTIVATED    PLANTS.  7 

Besides,  the  element  of  hazard  in  hunting  and 
fishing  attracts  primitive,  and  sometimes  civilized, 
man,  more  than  the  rude  and  regular  labor  of 
cultivation." 

Darwin  gives  us  in  the  book  quoted  above  an 
excellent  idea  of  the  beginnings  of  agriculture.1 
"MM.  Loiseleur-Deslongchamps  and  De  Candolle 
have  remarked,"  he  says,  "  that  our  cultivated 
plants,  more  especially  the  cereals,  must  origi- 
nally have  existed  in  nearly  their  present  state  ; 
for  otherwise  they  would  not  have  been  noticed 
and  valued  as  objects  of  food.  But  these  authors 
apparently  have  not  considered  the  many  accounts 
given  by  travellers  of  the  wretched  food  collected 
by  savages.  I  have  read  an  account  of  the  savages 
of  Australia  cooking,  during  a  dearth,  many  vege- 
tables in  various  ways,  in  the  .hopes  of  rendering 
them  innocuous  and  more  nutritious.  Dr.  Hooker 
found  the  half-starved  inhabitants  of  a  village  in 
Sikhim  suffering  greatly  from  having  eaten  arum- 
roots,  which  they  had  pounded  and  left  for  several 
days  to  ferment,  so  as  partially  to  destroy  their 
poisonous  nature  ;  and  he  adds  that  they  cooked 
and  ate  many  other  deleterious  plants.  Sir  Andrew 
Smith  informs  me  that  in  South  Africa  a  large 

1  Vol.  I.  p.  324, 


8  ORIGIN    OF    CULTIVATED    PLANTS. 

number  of  fruits  and  succulent  leaves,  and  espe- 
cially roots,  are  used  in  times  of  scarcity.  The 
natives,  indeed,  know  the  properties  of  a  long 
catalogue  of  plants,  some  having  been  found  dur- 
ing famines  to  be  eatable,  others  injurious  to 
health,  or  even  destructive  to  life.  He  met  a 
party  of  Baquanas,  who,  having  been  expelled  by 
the  conquering  Zulus,  had  lived  for  years  on  any 
roots  or  leaves  which  afforded  some  little  nutri- 
ment, and  distended  their  stomachs  so  as  to  relieve 
the  pangs  of  hunger.  Sir  Andrew  Smith  also 
informs  me  that  on  such  occasions  the  natives 
observe  as  a  guide  for  themselves,  what  the  wild 
animals,  especially  baboons  and  monkeys,  eat. 

"  From  innumerable  experiments  made  through 
dire  necessity  by  the  savages  of  every  land,  with 
the  results  handed  down  by  tradition,  the  nutri- 
tious, stimulating,  and  medicinal  properties  of  the 
most  unpromising  plants  were  probably  first  dis- 
covered. It  appears,  for  instance,  at  first  an  inex- 
plicable fact  that  untutored  man,  in  three  distant 
quarters  of  the  world,  should  have  discovered 
among  a  host  of  native  plants  that  the  leaves  of 
the  tea-plant  and  mattee,  and  the  berries  of  the 
coffee,  all  included  a  stimulating  and  nutritious 
essence,  now  known  to  be  chemically  the  same. 


Oil! GIN    OF    CULTIVATED    PLANTS.  9 

We  probably  owe  our  knowledge  of  the  uses  of 
almost  all  plants  to  man  having  originally  existed 
in  a  barbarous  state,  and  having  been  often  com- 
pelled by  severe  want  to  try  as  food  almost 
everything  which  he  could  chew  and  swallow. 

"  From  what  we  know  of  the  habits  of  savages 
in  many  quarters  of  the  world,  there  is  no  reason 
to  suppose  that  our  cereal  plants  originally  existed 
in  their  present  state  so  valuable  to  man.  Let  us 
look  to  one  continent  alone  ;  namely,  Africa.  Barth 
states  that  the  slaves  over  a  large  part  of  the  cen- 
tral region  regularly  collect  the  seeds  of  a  wild 
grass,  the  Pennisetum  disticlmm ;  in  another  dis- 
trict he  saw  women  collecting  the  seeds  of  a  Poa 
by  swinging  a  sort  of  basket  through  the  rich 
meadow-land.  Near  Tete,  Livingstone  observed 
the  natives  collecting  the  seeds  of  a  wild  grass ;  and 
farther  south,  as  Anderson  informs  me,  the  natives 
largely  use  the  seeds  of  a  grass  of  about  the  size 
of  canary  seed,  which  they  boil  in  water.  They 
eat  also  the  roots  of  certain  reeds ;  and  every  one 
has  read  of  the  Bushmen  prowling  about  and  dig- 
ging up  with  a  fire-hardened  stake  various  roots. 
Similar  facts  with  respect  to  the  collection  of  the 
seeds  of  wild  grasses  in  other  parts  of  the  world 
could  be  given. 


10  ORIGIN    OF    CULTIVATED    PLANTS. 

u  Accustomed  as  we  are  to  our  excellent  vegeta- 
bles and  luscious  fruits,  we  can  hardly  persuade 
ourselves  that  the  stringy  roots  of  the  wild  carrot 
and  parsnip,  or  the  little  shoots  of  the  wild  aspar- 
agus, or  crabs,  sloes,  and  so  forth,  should  ever  have 
been  valued ;  yet  from  what  we  know  of  the  hab- 
its of  Australian  and  South  African  savages,  we 
need  feel  no  doubt  on  this  head.  The  inhabitants 
of  Switzerland,  during  the  stone  period,  largely 
collected  wild  crabs,  sloes,  bullaces,  hips  of  roses, 
elderberries,  beech-mast,  and  other  wild  berries  and 
fruits.  Jemmy  Button,  a  Fuegian  on  board  the 
Beagle,  remarked  to  me  that  the  poor  and  acid 
black  currants  of  Terra  del  Fuego  were  too  sweet 
for  his  taste. 

"  The  savage  inhabitants  of  each  land,  having 
found  out  by  many  and  hard  trials  what  plants 
were  useful,  or  could  be  rendered  useful  by  various 
cooking  processes,  would  after  a  time  take  the  first 
step  in  cultivation  by  planting  them  near  their 
usual  abodes.  Livingstone  states  that  the  savage 
Batokas  sometimes  left  wild  fruit  trees  standing  in 
their  gardens  and  occasionally  even  planted  them, 
'  a  practice  seen  nowhere  else  among  the  natives.' 
But  Du  Chaillu  saw  a  palm  and  some  other  wild 
fruit  trees  which  had  been  planted ;  and  these  trees 


ORIGIN  OF  CULTIVATED  PLANTS.       11 

were  considered  private  property.  The  next  step 
in  cultivation  —  and  this  would  require  but  little 
forethought  —  would  be  to  sow  the  seeds  of  useful 
plants ;  and  as  the  soil  near  the  hovels  of  the 
natives  would  often  be  in  some  degree  manured, 
improved  varieties  would  sooner  or  later  arise. 
Or  a  wild  and  unusually  good  variety  of  a  native 
plant  might  attract  the  attention  of  some  wise  old 
savage ;  and  he  would  transplant  it,  or  sow  its 
seed." 


12  THE    COTTON    PLANT. 


II. 

THE    COTTON    PLANT.1 

Bv  NINA  MOORE. 

COTTON,  like  wheat,  is  older  than  history.  In 
the  time  of  Herodotus,  and  probably  long  before, 
the  people  of  India  wove  the  fibre  of  their  native 
species,  Gossypium  arboreum,  into  garments ;  for 
centuries  they  cultivated  around  the  Hindoo  tem- 
ples Gossypium  religiosum,  reserving  its  product 
for  the  tripartite  thread,  which,  as  a  symbol  of 
the  Brahmin  Trinity,  was  used  in  the  sacerdotal 
robes  of  the  priests. 

India  muslins  are  famed  for  their  beauty.  Tav- 
ernier  (1662)  says  that  some  of  the  muslins  or 

1  This  classification  of  the  species  of  Gossypium,  founded  on  that  of 
Linnaeus,  is  given  by  Parlatore  in  his  "  Le  Specie  dei  Cotoni." 
Gossypium  Arboreum  ;  native  of  India. 
"          Herbaceum. 
"          Religiosum. 

Barbadense  :  sea  island,  long-stapled  cotton ;    native  of 

the  Bahama  Islands. 
"          Hirsutum  :  Georgia,  upland,  short-stapled  cotton ;  native 

of  Mexico. 

"          Sandvichensis  ;  native  of  the  Sandwich  Islands. 
"          Taitensis ;  native  of  Tahiti. 


THE    COTTON    PLANT.  13 

"  calicuts  "  l  that  lie  saw  were  "  so  fine  that  you 
could  hardly  feel  them  in  your  hand."  The  Rev. 
William  Ward  goes  further  yet,  and  describes  a 
fabric  "  so  exceeding  fine  that  when  laid  on  the 


FIG.  I.     GOSSYPIUM    BARBADENSE   (Royle). 

grass  and  the  dew  has  fallen  on  it,  it  is  no  longer 
discernible."  The  looms  from  which  these  mar- 
vellous webs  emerged  were  of  the  most  primitive 
sort;  yet  when  they  disappeared,  under  the  ad- 

1  Calicut  was  a  town  on  the  Malabar  coast,  whence  cotton  cloth  was 
imported.     Our  word  calico  is  a  corruption  of  the  name. 


14  THE    COTTON    PLANT. 

vance  of  English  machinery,  the  skill  of  the  people 
became  almost  a  thing  of  the  past,  the  new  in- 
dustry having  quite,  obliterated  the  old. 

Abundant  as  India's  cotton  crop  has  always 
been,  that  of  America  surpasses  it.  India  stands 
second,  America  first,  among  the  cotton-producing 
countries  of  the  world. 

Columbus,  landing  on  San  Salvador  in  1492, 
and  touching  at  Guadeloupe  in  the  following  year, 
found  on  these  islands  a  rich  supply  of  cotton, 
in  all  likelihood  Gossypium  Barbadense  (Fig.  1), 
the  sea-island  or  long-stapled  cotton,  which  grows 
wild  on  the  Bahamas  at  the  present  day.  For  a 
mere  bagatelle  he  bought  as  much  as  he  could, 
and  carried  it  back  with  him  to  the  Old  World. 

Another  species,  Gossypium  hirsutum  (Fig.  2), 
Upland,  Georgia,  or  short-stapled  cotton,  grew  upon 
the  mainland  of  North  America.  Cortez  found  it 
in  Mexico.  He  obtained  from  the  Aztecs  good 
cloth  of  their  own  manufacture,  and  sent  home  to 
Charles  V.,  of  Spain,  "  cotton  mantles,  some  all 
white,  others  mixed  with  white  and  black,  or  red, 
green,  yellow,  and  blue." 

These  long-staple  and  short-staple  cottons,  Gos- 
sypium Barbadense  and  Gossypium  hirsutum,  of 
the  Bahamas  and  of  Mexico,  were  early  introduced 


THE    COTTON    PLANT.  15 

into  Virginia  and  Georgia.  It  was  in  1621  that 
some  cotton  seeds,  probably  of  Grossypium  Barba- 
dense  from  the  West  Indies,  were  planted  in  Vir- 
ginia as  an  experiment.  In  1739  a  Swede  named 
Samuel  Auspourguer,  who  had  cultivated  cotton  in 


FIG.  2.     GOSSYPIUM    HIRSUTUM    (Royle). 

Georgia,  carried  a  sample  of  his  fibre  to  England. 
After  that,  small  but  increasing  quantities  were 
sent  over  yearly  until  cotton  became  the  most  im- 
portant export  of  the  South. 

In  1792  the  cotton  sent  from  the  United  States 
to   Liverpool   amounted    to   138,328   pounds.     In 


16  THE    COTTON    PLAtfT. 

1794  the  amount  rose  to  1,601,700  pounds.  The 
cause  of  this  tremendous  increase,  and  the  still 
greater  increase  that  followed,  was  the  invention, 
in  1793,  of  the  cotton  gin. 

The  cotton  fibre  grows  on  the  seed,  and  is  firmly 
adherent  to  the  testa.  To  separate  seed  and  fibre 
by  hand  had  been  a  slow  and  laborious  task.  The 
cotton  gin,  invented  by  Eli  Whitney,  was  a  machine 
by  means  of  which,  as  Mr.  George  Emerson  has 
said,  "a  new  era  in  the  culture  of  cotton  was 
established,  three  hands  assisted  by  water  power 
being  now  able  to  separate,  in  the  same  time,  as 
much  cotton  from  its  seed  as  would  before  have 
required  three  thousand  pairs  of  hands." 

At  that  time  the  planting,  the  hoeing,  and  the 
gathering  of  the  cotton  crop  was  the  work  of  the 
Southern  negroes.  They  also  prepared  the  fibre 
for  the  market.  The  cotton  gin,  while  relieving 
them  of  the  latter  task,  increased  the  demand  for 
their  services  in  the  fields ;  for,  as  immense  quanti- 
ties of  cotton  could  now  be  furnished  to  all  parts 
of  the  United  States  and  Europe,  a  large  supply 
must  be  sown  and  tended.  It  was  a  striking  in- 
stance of  the  action  of  machinery  in  cutting  down 
the  sum  of  hand  labor  required  at  one  point  only 
to  raise  it  an  hundred-fold  at  another.  Field- 


THE    COfTOK   PLANT.  17 

hands  were  in  great  demand,  and  the  immediate 
effect  of  the  invention  of  the  cotton  gin  was  the 
tightening  of  the  bonds  of  the  slave.  Slave  labor 
became  all  in  all  to  the  planters  of  the  South. 
Northern  men  were  afraid  to  meddle  in  the  in- 
terest of  humanity  when  the  interests  of  King 
Cotton  were  at  stake.  It  was  declared,  and  came 
to  be  believed,  that  negro  labor  only  was  available 
in  those  blazing  cotton  fields,  and  that  only  as 
slaves  could  negroes  be  forced  to  work.  Events 
have  abundantly  proved,  however,  that  free  labor 
is  not  injurious  to  cotton ;  white  men,  as  well  as 
negroes,  are  now  employed  in  its  culture,  and  the 
crop  is  larger  than  ever. 

In  the  United  States  census  report  for  1884, 
Mississippi  stands  first  among  cotton  -  producing 
States.  Its  particularly  rich  soil  yields  cotton  at 
the  rate  of  eight-tenths  of  a  bale  per  capita  yearly. 

Both  kinds  of  cotton,  the  long-stapled  and  the 
short-stapled  species,  are  planted  in  Mississippi. 
As  soon  as  the  frost  is  out  of  the  ground  the  cotton 
stalks  of  the  preceding  year  are  knocked  down  and 
cleared  away,  or  sometimes  burned  and  plowed 
under.  The  field  is  then  scored  in  long  furrows, 
four  or  five  feet  apart  in  the  best  soil,  where  the 
plants  may  be  expected  to  grow  large ;  three  or 


18  THE    COTTON    PLANT. 

four  feet  apart  in  poorer  ground,  where  less  grow- 
ing room  is  needed. 

Between  the  middle  of  March  and  the  middle  of 
May  planting  is  in  order.  The  seeds  are  dropped 
into  the  furrows,  either  by  hand  or  by  a  machine 
called  a  planter,  and  then  lightly  covered  with 
about  an  inch  of  soil.  When  the  "  stand,"  as 
the  collection  of  young  plants  is  called,  is  fairly 
up,  and  from  six  to  ten  inches  high,  the  thinning 
out  begins.  The  weaker  plants  are  relentlessly 
hoed  down,  the  stronger  ones  are  left  standing  at 
intervals  of  twelve  or  eighteen  inches ;  and  before 
long  these  are  subjected  to  the  process  of  topping ; 
that  is,  the  uppermost  bud  of  each  is  clipped  off, 
and  the  plant,  unable  to  continue  its  main  shoot, 
sends  out  numerous  side-branches  to  make  up  for 
its  deficiency.  As  all  of  these  side-branches  bear 
blossoms  and  fruit,  the  planter's  purpose,  that  of 
increasing  his  supply  of  fibre,  is  accomplished. 

The  flowers  appear  when  the  plant  is  from 
twenty-four  to  thirty-six  inches  high,  and  the  bolls 
open  about  six  weeks  after  the  corolla  has  fallen. 

Though  the  cotton  plant  is  a  biennial  or  a  per- 
ennial, it  is  always  treated  as  an  annual ;  the  old 
plants  are  removed  and  new  seeds  sown  each 
spring.  W.  B.  Dana,  in  his  "  Cotton  from  Seed  to 


THE    COTTON    PLANT.  19 

Loom,"  says  :  "  A  cotton  seed  is  something  like  a 
bean  in  its  early  growth.  Within  it  are  two  leaves 
and  a  tap-root ;  and  after  lying  in  the  ground  about 
a  week  the  tap-root  strikes  down  into  the  earth, 
while  the  two  leaves  open  above,  growing  in  a  few 
days  from  two  to  three  inches  high.  .  .  .  During 
the  next  ten  days  two  more  leaves  appear,  and  in 
the  following  two  weeks  from  five  to  six  additional 
ones.  .  .  .  When  the  cotton  plant  is  about  twelve 
inches  high  it  begins  to  throw  out  limbs,  with 
leaves  about  four  inches  apart,  having  at  every 
joint  a  form,  or  square,  or  shape  —  all  these  names 
being  used  for  what  is  really  the  bud. 

"  This  bud,  on  its  first  appearance,  is  triangu- 
lar in  outline,  with  three  leafy  bracts  on  the  out- 
side. .  .  .  The  blossom  opens  after  sunrise  in  the 
morning,  pure  white,  with  three  (or  four,  or  five) 
petals.  It  begins  to  close  at  about  two  o'clock 
when  a  pale  red  streak  may  be  seen  running  up 
each  petal,  and  at  sundown  it  is  wholly  closed. 
The  next  morning,  at  about  sunrise,  it  is  again 
open,  as  fresh  as  ever,  but,  instead  of  being  white, 
it  is  now  a  beautiful  pink.  It  lasts  the  day  out, 
but  with  the  setting  sun  again  closes,  this  time, 
however,  wilting  and  falling  off,  leaving  at  its 
base  a  little  boll  about  the  size  of  a  small  bean." 


20  THE   COTTON   PLANT. 

The  boll  is  filled  with  young  seeds,  surrounded 
by  a  white  pulp-like  substance.  As  the  boll  ma- 
tures, the  pulp  disappears,  and  the  cavity  becomes 
wholly  crowded  with  the  densely  packed  silky 
hairs,  which  have  grown  from  the  thick  coats  of 
the  seeds.  The  pressure  of  these  soft  hairs  as 
they  expand,  finally  overcomes  the  resistance  of 
the  seed  vessel ;  the  valves  part 
(Fig.  3),  and  the  beautiful  white 
cotton,  spreading  as  it  comes  in 
contact  with  the  air,  hangs  out 
in  snowy  "locks"  several  inches 
long. 

The  sooner  it  is  picked,  now, 
FIG.  3.  BOLL  OF  COTTON  the  better.  Exposure  to  the 
weather  darkens  and  weakens 
the  fibre.  Picking  begins  in  the  middle  of  August, 
and  does  not  end  until  the  last  of  September.  "  The 
picking  is  performed,"  writes  Mr.  George  Emerson, 
"  by  male  and  female  hands  provided  with  Osna- 
burgh  bags,  hung  over  the  neck  and  shoulders, 
into  which  the  cotton  is  put  as  fast  as  picked. 
These,  when  full,  are  emptied  into  large  Osnaburgh 
sheets,  placed  at  convenient  spots ;  the  sheets  are 
carried  home  in  the  afternoon.  One  hand  can  pick 
about  one  hundred  pounds  per  day  of  seed  cotton." 


THE    COTTON    PLANT.  21 

Having  been  gathered,  the  cotton  is  spread  out 
to  dry,  and  when  thoroughly  dried  is  ready  to  be 
ginned  for  the  market.  Whitney's  cotton  gin  con- 
sists of  a  hopper,  in  which  the  cotton  is  confined, 
and  a  roller  thickly  set  with  circular  saws.  One 
side  of  the  hopper  has  bars,  adjusted  to  admit  the 
edges  of  the  saws,  but  so  close  together  that  when 
the  saw  teeth  catch  the  cotton  fibres,  and  pull  them 
out  of  the  hopper,  the  seeds  are  held  by  the  bars 
and  remain  behind.  Stiff  brushes  then  take  the 
cotton  from  the  saws ;  it  is  passed  between  heavy 
rollers,  and  comes  out  in  loose,  flat  sheets.  Other 
gins,  different  in  construction,  are  also  used. 

The  sheets  which  come  from  the  gin  are  rolled 
in  bales,  not  less  than  four  hundred  pounds  in 
weight;  the  bale  cotton  is  afterward  cleaned, 
carded,  drawn  into  a  coarse,  loose  thread,  and 
then  spun  into  stout  or  delicate  yarns,  as  the  need 
may  be. 

The  great  usefulness  of  cotton  depends,  as  will 
be  shown  by  the  following  extract  from  Edwin 
Lancaster's  "  Remarks  on  the  Natural  History  of 
Cotton,"  on  its  power  of  forming  a  twist.  "  The 
cotton  fibre  is  a  hair :  it  does  not,  however,  grow 
on  the  surface  of  the  plant.  ...  It  is  not  the 
length  or  strength  of  the  hair  alone  which  gives  to 


22 


THE    COTTON    PLANT. 


it  the  power 
twisted.     If 


FIG.  4.  aandc,  Mag- 
nified Drawings  of 
Cotton  Fibre  ;  b,  the 
Same,  from  some 
Unravelled  Threads 
of  Cotton  Cloth 
(Royle). 

the  hair  give 
a  flat  ribbon, 


it  possesses  of  forming  a  thread  when 
examined  under  the  microscope,  the 
cotton  hair  will  be  found  ap- 
parently to  consist  of  two  deli- 
cate, transparent  tubes,  the  one 
twisted  round  the  other,  so  as 
to  have  the  appearance  of  two 
pieces  of  cord  wound  round 
each  other  (Fig.  4).  If,  how- 
ever, the  hair  be  examined  in 
its  young  state,  it  will  be 
found  to  be  an  untwisted, 
cylindrical  tube.  It  is  during 
its  growth  that  this  change 
takes  place.  As  the  seeds  and 
hairs  grow,  the  capsules  do  not 
appear  to  expand  with  equal 
rapidity ;  and,  consequently, 
the  hair  is  exposed  to  pressure 
on  all  sides.  The  result  of 
this  is,  that  the  hair  collapses 
in  the  middle,  leaving  a  half- 
formed  tube  on  each  side. 
These  uncollapsed  portions  of 
it  the  '  appearance,'  says  Bauer,  '  of 
with  a  hem  or  border  at  each  edge.' 


THE    COTTON    PLANT.  23 

The  hair  does  not,  however,  grow  out  straight,  but 
coming  in  contact  with  other  hairs,  and  the  sides 
of  the  capsule  or  fruit,  it  becomes  twisted ;  thus 
acquiring  the  appearance  first  described,  of  two 
cords  twisted  together.  This  twisting  is  undoubt- 
edly the  great  fact  that  makes  the  cotton  hairs  of 
value  to  man.  There  are  many  hairs,  such  as 
those  of  the  cotton-grass  and  the  bombax,  which 
are  as  long,  and  apparently  as  strong,  as  those  of 
the  Gossypium,  but  which,  failing  in  this  irregu- 
larity of  their  surface,  are  utterly  incapable  of 
being  twisted  into  a  thread  or  yarn." 

Of  the  seeds  discarded  by  the  cotton  gin,  a  small 
proportion  are  needed  for  sowing.  The  remainder 
were  formerly  used  for  enriching  the  land.  They 
are  now,  however,  turned  to  better  account.  The 
oil  which  they  contain,  cotton-seed  oil,  is  valuable 
for  cooking  purposes ;  it  forms  a  good  substitute 
for  olive  oil,  or  for  lard ;  it  is  also  excellent  for 
making  soap,  and  for  mixing  paints.  *  The  com- 
pact mass  which  is  left,  after  the  oil  has  been 
pressed  out,  is  sold  as  cotton-seed  cake,  and  fed  to 
cows  and  sheep. 


24  SEED-FOOD. 


III. 

SEED-FOOD. 

BY  FREDERICK  LE!IOY  SARGENT. 

IN  the  study  of  animals  we  find  that  as  we 
advance  from  the  lower  to  the  higher  forms,  there 
is  a  wonderful  improvement  in  the  way  the  young 
are  cared  for.  It  is  the  same  with  plants,  and  in 
those  higher  forms  which  produce  flowers  and 
seeds  the  provisions  made  for  the  welfare  of  off- 
spring afford  some  of  the  greatest  marvels  of  vege- 
table life. 

One  of  the  most  direct  and  obvious  ways  in 
which  the  well-being  of  infant  plants  is  promoted 
is  by  the  store  of  food  that  is  laid  up  in  the  seeds. 
This  enables  the  sprouting  seedling  to  develop 
root  and  leaves  before  it  is  thrown  entirely  upon 
its  own  resources ;  and  thus  from  the  start  the 
plantlet  can  work  to  advantage. 

The  amount  of  this  seed-food  varies  of  course 
very  greatly,  as  we  have  all  sizes  of  seeds  from  the 
tiniest  atoms  up  to  such  large  ones  as  coco-nuts.1 

1  More  commonly  but  less  correctly  written  "  cocoanuts."  —  See 
Imperial  Dictionary. 


SEED-FOOD.  25 

But  what  is  more  interesting  is  that  the  amount  of 
space  occupied  by  the  embryo,  as  compared  with 
the  amount  of  space  filled  by  the  seed-food  sur- 
rounding it,  is  also  very  different  in  different  seeds. 
In  some  cases,  as  for  example  in  the  coco-nut,  the 
nutmeg,  and  the  date  seed,  the  embryo  is  a  mere 
speck  embedded  in  copious  seed-food,  much  as  in  a 
hen's  egg  the  germ  of  the  chick  is  surrounded  by 
the  yolk  and  albumen.  This  resemblance  sug- 
gested to  botanists  the  name  albumen  as  a  good 
one  to  use  for  the  seed-food  which  accompanies  an 
embryo.  In  other  seeds  such  as  those  of  maize, 
morning-glory,  and  the  castor-oil  plant,  we  find  a 
medium-sized  embryo  and  a  moderate  amount  of 
albumen;  such  might  be  compared  to  an  egg  in 
which  the  chick  had  become  partly  developed  at 
the  expense  of  the  surrounding  food.  Finally  there 
are  many  seeds  which  like  peanuts,  almonds,  and 
chestnuts,  are  destitute  of  albumen  ;  but  these  have 
the  space  within  the  shell  filled  by  a  well-developed 
embryo,  more  or  less  gorged  with  food,  and  here 
we  have  something  to  remind  us  of  an  egg  just 
ready  to  hatch.  In  every  case  the  plantlet  gets 
all  the  food  sooner  or  later,  the  only  difference 
being  that  some  have  to  absorb  more  or  less  at  the 
time  of  germination,  while  with  others  the  entire 


26  SEED-FOOD. 

food-supply  is  deposited  within  the  embryo  during 
the  formation  of  the  seed. 

In  the  various  kinds  of  eggs  there  is  scarcely 
any  difference  in  the  nature  of  the  food-supply. 
Chemically  considered,  the  contents  of  a  hen's  egg 
is  practically  the  same  as  that  of  other  eggs.  It- 
is  not  so,  however,  with  the  food-supply  of  seeds, 
for  very  various  substances  are  made  use  of  by 
different  plants.  Among  these  the  most  important 
are  starch,  oils,  and  albuminoids. 

Starch  forms  about  a  third  of  the  bulk  of  beans 
and  peas  ;  from  half  to  two-thirds  of  wheat,  oats, 
rye,  and  barley ;  and  over  four-fifths  of  maize  and 
rice.  It  is  very  much  like  sugar  in  its  chemical 
composition,  and  has  about  the  same  value  as  a 
food. 

Oil  occurs  in  small  quantities  along  with  the 
starch  in  the  seeds  just  mentioned,  but  in  many 
cases  it  entirely  replaces  the  starch,  and  forms  the 
principal  part  of  the  seed-food.  Peanuts  and  cot- 
ton seeds,  for  example,  are  very  rich  in  an  oil 
which  is  extensively  used  as  a  substitute  for  that 
obtained  from  olives.  Walnut  oil  is  put  to  the 
same  use.  Flaxseeds  afford  the  linseed  oil  so  val- 
uable as  a  medium  for  mixing  paints.  The  albu- 
men of  the  coco-nut  when  boiled  and  pressed  yields 


SEED-FOOD.  27 

two  fatty  substances  :  one,  called  stearine,  is  solid 
at  ordinary  temperatures,  and  is  used  in  the  manu- 
facture of  candles  ;  the  other,  being  liquid,  is  burned 
in  lamps,  or  when  fresh  is  used  in  cookery.  Some 
of  our  most  valued  nuts,  such  as  the  butternut, 
hickory,  pecan-nut,  Brazil-nut,  pistachio-nut  and 
almond,  owe  their  rich  flavor  to  the  abundant  oil 
they  contain. 

In  point  of  nutritive  value  the  albuminoids  form 
by  far  the  most  important  constituents  of  seed- 
food,  for  in  chemical  composition  they  are  very 
similar  to  egg-albumen.  No  seeds  are  entirely 
destitute  of  albuminoids,  but  as  a  rule  the  quan- 
tity is  not  very  large.  In  the  cereals  the  propor- 
tion ranges  from  seven  and  one-half  per  cent  in 
rice  to  nineteen  per  cent  or  more  in  wheat.  Peas 
and  beans  are  the  most  nutritious  seeds  that  we 
commonly  use,  as  about  one  quarter  of  their  bulk 
is  albuminoid  material.  The  value  of  wheat  is 
greatly  enhanced  by  the  fact  that  its  albuminoid 
food  consists  almost  wholly  of  gluten.  This  sub- 
stance it  is  which  imparts  to  macaroni  its  peculiar 
firmness  and  elasticity,  and  which  gives  to  wheaten 
dough  that  tenacity  upon  which  the  making  of 
raised  bread  depends. 

Of  all  the  sorts  of  food  which  plants  lay  by  in 


28  SEED-FOOD. 

special  organs  as  a  reserve  for  the  future,  seed- 
food  is  the  most  compact,  as  it  is  the  freest  from 
water;  for  the  same  reason  it  is  least  liable  to 
change  with  long  keeping,  and  from  the  larger 
proportion  of  albuminoids  contained  it  is  the  most 
nutritious.  This  has  led  man  from  the  earliest 
times  to  use  seeds  as  the  chief  source  of  their  veg- 
etable food ;  many  of  the  very  kinds  whose  seed- 
food  we  appropriate  nourished  men  ages  before  the 
pyramids  were  built.  The  evidences  which  have 
come  down  to  us  of  their  earliest  use  are  fragmen- 
tary, but  they  clearly  show  that  these  productions 
must  have  been  of  the  utmost  value  to  the  men  of 
those  days,  and  they  are  well  calculated  to  impress 
the  mind  with  a  sense  of  the  importance  to  human 
life  of  plants  which  have  afforded  the  best  food 
from  prehistoric  times  to  the  present  day. 

We  learn  from  De  Candolle  that  some  of  the 
most  ancient  Egyptian  monuments,  older  than  the 
Hebrew  Scriptures,  show  the  cultivation  of  wheat 
already  established,  and  when  the  Egyptians  or 
Greeks  speak  of  its  origin,  they  attribute  it  to  the 
mythical  personages  Isis,  Ceres,  or  Triptolemus. 
One  interesting  discovery  of  the  Egyptologists  was 
the  finding  of  a  grain  of  wheat  embedded  in  a 
brick  of  the  pyramid  of  Dash  our,  to  which  the 


SEED-FOOD.  29 

date  3359  B.C.  has  been  assigned.  There  is  also 
evidence  of  the  cultivation  of  barley,  millet,  and  a 
kind  of  lupin,  in  Egypt  during  prehistoric  times. 
Herodotus  tells  us  that  the  lentil  was  largely  used 
by  the  ancient  Egyptians,  but  because  they  con- 
sidered it  common  and  coarse  it  found  no  place 
upon  their  monuments.  The  red  pottage  for 
which  Esau  sold  his  birthright  was  made  of 
lentils,  the  color  being  due  in  all  probability  to  the 
seeds  having  been  hulled,  thus  exposing  the  pale- 
red  kernels.  It  is  still  the  practice  in  that  region 
to  cook  lentils  in  this  way. 

The  occurrence  of  Sanskrit  names  for  the  lentil, 
chick-pea,  barley,  millet,  walnut,  sesame,  and  cas- 
tor-oil plant,  indicate  a  very  ancient  use  in  India. 

It  is  recorded  that  the  Chinese  Emperor  Chin- 
nong,  who  lived  about  2700  B.C.  instituted  the 
annual  ceremony  of  sowing  seeds  of  the  five  most 
important  plants  of  the  Empire,  as  a  token  of 
appreciation  and  gratitude  for  these  gifts  of 
Heaven.  The  plants  chosen  were  rice,  wheat, 
sorghum,  a  sort  of  millet,  and  a  bean-like  plant 
known  as  soy,  from  which  substances  similar  to 
butter  and  cheese  are  largely  extracted.  No  less 
a  personage  than  a  prince  of  the  royal  blood  can 
take  part  in  the  ceremony,  and  the  planting  of  the 


30  SEED-FOOD. 

rice  seeds  must  be  performed  by  the  emperor  him- 
self. When  we  realize  that  rice  gives  food  to 
more  human  beings  than  any  other  plant,  it  is 
not  difficult  for  us  to  sympathize  with  the  feeling 
that  prompts  such  special  consideration  for  this 
invaluable  grain. 

At  a  time  probably  anterior  to  the  Trojan  War, 
before  the  dawn  of  European  history,  there  lived 
in  the  region  of  Switzerland  a  half-savage  people, 
of  whose  existence  we  know  from  remains  of  their 
dwellings  which  have  been  discovered  in  the  lakes. 
Along  with  primitive  implements  of  stone  or 
bronze  have  been  found  the  seeds  of  wheat,  two 
kinds  of  barley,  oats,  lentils,  and  our  common 
garden  pea. 

Early  Grecian  coins  and  passages  from  the  an- 
cient writers  show  that  the  lentil,  chick-pea,  gar- 
den pea,  millet,  and  wheat  were  well  known  to 
the  Greeks.  Barley  was  highly  prized  by  them  as 
a  strong  food  for  athletes  in  training,  and  they 
often  represented  the  goddess  Ceres  with  ears  of 
this  grain  plaited  in  her  hair.  A  six-rowed  variety 
of  barley  is  pictured  upon  medals  of  the  Italian 
town  Metapontis,  which  date  from  about  600  B.C. 

Some  of  our  most  valued  seed  plants  are  pro- 
ducts of  our  own  country,  and  were  found  in  ex- 


SEED-FOOD.  31 

tensive  cultivation  by  Columbus  and  his  followers. 
Cacao l  was  largely  used,  and  so  highly  prized  that 
the  seeds  served  as  money.  The  peanut,  now 
widely  cultivated  in  many  parts  of  the  world,  is 
in  all  probability  a  native  of  tropical  America,  and 
the  fact  that  seeds  of  the  plant  have  been  found  in 
ancient  Peruvian  tombs  at  Ancon,  gives  evidence 
of  use  in  quite  early  times.  In  these  same  tombs 
have  been  found  seeds  of  the  Lima-bean  and  our 
common  pole-bean.  By  far  the  most  important  of 
American  vegetable  products  is  the  maize  or  Indian 
corn,  and  we  have  abundant  proof  of  its  very 
ancient  and  widespread  cultivation.  Aboriginal 
burial  mounds,  the  tombs  of  the  Incas,  and  the 
catacombs  of  Peru  have  been  found  to  contain 
ears  or  grains  of  maize.  Just  as  the  ancient  Greeks 
offered  the  first  fruits  of  their  grain  harvest  to  the 
goddess  Ceres,  so  the  Aztecs  brought  to  their 
goddess  Cinteuil  the  first  ears  from  their  maize 
fields.  Although  this  old  Mexican  custom  may 
not  antedate  the  Christian  era,  still  the  develop- 
ment of  such  a  ceremony  must  have  been  preceded 
by  a  long  period  of  widespread  use. 

With  many  plants  provision  is  made  for  defend- 

1  More  commonly  but  less  correctly  written  "cocoa." — See  Im- 
perial Dictionary. 


32  SEED-FOOD. 

ing  the  seed-food  against  the  depredations  of  seed- 
eating  animals ;  but  strange  to  say,  some  of  the 
most  effective  of  these  means  of  defence  constitute 
the  very  attractions  which  lead  to  our  using  the 
seeds.  For  example,  it  is  probable  that  no  wild 
animal  would  think  of  eating  mustard  seeds  —  at 
least  a  second  time.  Nutmegs  are  quite  as  well 
protected  by  the  aromatic  oil  which  many  of  us 
prize  so  highly,  but  which  is  probably  distasteful 
to  animals,  and  if  taken  in  quantity  is  poisonous. 
To  a  certain  extent  the  same  is  true  of  coffee  and 
cacao  seeds,  both  of  which  are  decidedly  unpalata- 
ble in  the  raw  state. 

Certain  seeds  containing  the  most  virulent  poi- 
sons afford  drugs  which  are  often  of  great  value 
in  medicine.  Nux  vomica,  for  example,  yields  the 
important  drug  strychnine.  The  seeds  of  larkspur, 
foxglove,  lobelia,  henbane,  sabadilla,  colchicum, 
stramonium,  croton  and  bitter-almond  are  each 
rich  in  some  powerful  medicinal  principle. 

Perhaps  the  most  curious  expedient  resorted  to 
for  protection  is  hardening  the  seed-food  to  an 
extent  which  will  defy  the  best  of  teeth.  A  good 
example  of  this  is  the  ivory-nut,  which  is  largely 
imported  from  South  America,  and  its  albumen 
used  as  a  substitute  for  animal  ivory  in  the  manu- 


SEED-FOOD.  33 

facture  of  buttons,  knobs,  toys,  and  other  small 
articles.  The  same  hardening  of  albumen  occurs 
in  the  coquilla-nuts  of  Brazil,  and  causes  them  to 
be  in  much  demand  for  making  door  knobs,  um- 
brella handles,  and  such  articles  of  turnery. 

Besides  the  substances  we  have  mentioned  as 
being  contained  in  seeds  there  are  others,  such  as 
alcohol  and  certain  sugars  which  are  obtained  from 
seeds  by  inducing  chemical  changes  in  their  con- 
tents. To  consider  these  artificial  products  would 
lead  us  too  far  from  our  subject,  for  a  proper  under- 
standing of  the  processes  of  manufacture  would 
carry  us  deep  into  chemistry,  and  what  is  more, 
the  substances  so  produced  are  not  seed-food. 


34  MOVEMENTS    OF    SEEDLINGS. 


IV. 

MOVEMENTS    OF    SEEDLINGS. 

THE  tips  of  all  young  growing  parts  of  the 
higher  plants  continually  revolve,  bowing  succes- 
sively towards  every  point  of  the  compass.  Dar- 
win calls  this  movement  circumnutation.  In  the 
introduction  to  his  book/  "  The  Power  of  Move- 

1  "  The  Power  of  Movement  in  Plants "  was  published  in  1880. 
Darwin  had  previously  published,  in  1875,  an  essay  on  "  Climbing 
Plants,"  in  which  he  had  shown  that  the  young  tips  of  twining  stems, 
tendrils,  leaf-stalks,  etc.,  continually  revolve,  and  that  this  movement 
is  the  immediate  cause  of  their  twining.  The  later  work  extends  this 
conception  to  the  tips  of  all  young  growing  parts  of  plants.  In  his 
autobiography,  Darwin  says,  "In  accordance  with  the  principle  of 
evolution  it  was  impossible  to  account  for  climbing  plants  having 
been  developed  in  so  many  widely  different  groups,  unless  all  plants 
possess  some  slight  power  of  movement  of  an  analogous  kind.  This  I 
proved  to  be  the  case,  and  I  was  further  led  to  a  rather  wide  general- 
izationj  viz.,  that  the  great  and  important  classes  of  movements  excited 
by  light,  the  attraction  of  gravity,  etc.,  are  all  modified  forms  of  the 
fundamental  movement  of  circumnutation.  It  has  always  pleased  me 
to  exalt  plants  in  the  scale  of  organized  beings ;  and  I  therefore  felt 
an  especial  pleasure  in  showing  how  many  and  what  admirably  well 
adapted  movements  the  tip  of  a  root  possesses." 

The  conclusions  of  this  book  have  not  been  generally  accepted,  and 
have  met  with  much  criticism,  especially  in  Germanyo  Francis  Darwin 
says  ("Life  and  Letters  of  Charles  Darwin,"  II.  p.  502),  "The  central 
idea  of  the  book  is,  that  the  movements  of  plants  in  relation  to  light, 
gravitation,  etc.,  are  modifications  of  a  spontaneous  tendency  to  revolve 


MOVEMENTS    OF    SEEDLINGS.  35 

ment  in  Plants,"  he  says,1  "  The  chief  object  of 
the  present  work  is  to  describe  and  connect  to- 
gether several  large  classes  of  movement,  common 
to  almost  all  plants.  The  most  widely  prevalent 
movement  is  essentially  of  the  same  nature  as  that 
of  the  stem  of  a  climbing  plant,  which  bends  succes- 
sively to  all  points  of  the  compass,  so  that  the  tip 
revolves.  This  movement  has  been  called  by  Sachs 
c  revolving  nutation,'  but  we  have  found  it  much 
more  convenient  to  use  the  terms  circumnutation 
and  circumnutate.  As  we  shall  have  to  say  much 
about  this  movement,  it  will  be  useful  here  briefly 
to  describe  its  nature.  If  we  observe  a  circum- 
nutating  stem,  which  happens  at  the  time  to  be 
bent,  we  will  say  towards  the  north,  it  will  be  found 
gradually  to  bend  more  and  more  easterly,  until  it 
faces  the  east ;  and  so  onwards  to  the  south,  then 
to  the  west,  and  back  again  to  the  north.  If  the 
movement  had  been  quite  regular,  the  apex  would 

or  circumnutate,  which  is  widely  inherent  in  the  growing  parts  of 
plants.  This  conception  has  not  been  generally  adopted,  and  has  not 
taken  a  place  among  the  canons  of  orthodox  physiology." 

Nevertheless  the  book  is  one  of  exceeding  interest.  One  critic  has 
said,  "  No  one  can  doubt  the  importance  of  what  Mr.  Darwin  has  done, 
in  showing  that,  for  the  future,  the  phenomena  of  plant  movement  can, 
and  indeed  must  be,  studied  from  a  single  point  of  view." 

1  "  The  Power  of  Movement  in  Plants."  By  Charles  Darwin  and 
Francis  Darwin.  New  York :  D.  Appleton  &  Co.  1888.  p.  1.  The 
references  in  this  chapter  are  all  to  this  work. 


36  MOVEMENTS    OF    SEEDLINGS. 

have  described  a  circle,  or  rather,  as  the  stem  is 
always  growing  upwards,  a  circular  spiral.  But  it 
generally  describes  irregular  elliptical  or  oval  fig- 
ures ;  for  the  apex,  after  pointing  in  any  one  direc- 
tion, commonly  moves  back  to  the  opposite  side, 
not,  however,  returning  along  the  same  line.  .  .  . 

"  In  the  course  of  the  present  volume  it  will  be 
shown  that  apparently  every  growing  part  of  every 
plant  is  continually  circumnutating,  though  often 
on  a  small  scale.  Even  the  stems  of  seedlings 
before  they  have  broken  through  the  ground,  as 
well  as  their  buried  radicles,  circumnutate  as  far 
as  the  pressure  of  the  surrounding  earth  permits. 
In  this  universally  present  movement  we  have 
the  basis  or  groundwork  of  the  acquirement,  ac- 
cording to  the  requirements  of  the  plant,  of  the 
most  diversified  movements.  Thus,  the  great 
sweeps  made  by  the  stems  of  twining  plants,  and 
by  the  tendrils  of  other  climbers,  result  from  a 
mere  increase  in  the  amplitude  of  the  ordinary 
movement  of  circumnutation."  1 

After  minute  descriptions  of  many  experiments 
on  the  movements  of  radicles  and  cotyledons  of 
seedlings,  he  says  :  — 

"  In  all  the  germinating  seeds  observed  by  us, 
i  p.  3. 


MOVEMENTS    OF    SEEDLINGS.  37 

the  first  change  is  the  protrusion  of  the  radicle, 
which  immediately  bends  downwards  and  endeav- 
ors to  penetrate  the  ground.  In  order  to  effect 
this,  it  is  almost  necessary  that  the  seed  should 
be  pressed  down  so  as  to  offer  some  resistance, 
unless  indeed  the  soil  is  extremely  loose ;  for 
otherwise  the  seed  is  lifted  up,  instead  of  the  radi- 
cle penetrating  the  surface.  But  seeds  often  get 
covered  by  earth  thrown  up  by  burrowing  quad- 
rupeds or  scratching  birds,  by  the  castings  of 
earthworms,  by  heaps  of  excrement,  the  decaying 
branches  of  trees,  etc.,  and  will  thus  be  pressed 
down ;  and  they  must  often  fall  into  cracks  when 
the  ground  is  dry,  or  into  holes.  Even  with  seeds 
lying  on  the  bare  surface,  the  first  developed  root- 
hairs,  by  becoming  attached  to  stones  or  other 
objects  on  the  surface,  are  able  to  hold  down  the 
upper  part  of  the  radicle,  whilst  the  tip  penetrates 
the  ground.  .  ."  l  This  is  well  seen  in  the  germina- 
tion of  Clover. 

"  The  tip  of  the  radicle,  as  soon  as  it  protrudes 
from  the  seed-coats,  begins  to  circumnutate,  and 
the  whole  growing  part  continues  to  do  so,  prob- 
ably for  as  long  as  growth  continues.  ..." 

Then  conies  into  play  the  action  of  gravitation, 

1  p.  69. 


38  MOVEMENTS    OF    SEEDLINGS. 

which  causes  the  root  to  bend  downwards  towards 
the  centre  of  the  earth.  This  bending  is  called 
geotropism,  from  two  Greek  words  meaning,  "  the 
earth,"  and  "  to  turn." 

"Sensitiveness  to  gravitation,"  says  Darwin, 
speaking  of  the  radicle  of  the  seedling,  "  resides  in 
the  tip ;  and  it  is  the  tip  which  transmits  some 
influence  to  the  adjoining  parts,  causing  them  to 
bend.  As  soon  as  the  tip,  protected  by  the  root- 
cap,  reaches  the  ground,  it  penetrates  the  surface, 
if  this  be  soft  or  friable,  and  the  act  of  penetration 
is  apparently  aided  by  the  rocking  or  circumnu- 
tating  movement  of  the  whole  end  of  the  radicle.1 

"  After  the  tip  has  penetrated  the  ground  to  a 
little  depth,  the  increasing  thickness  of  the  radicle, 
together  with  the  root-hairs,  hold  it  securely  in  its 
place ;  and  now  the  force  exerted  by  the  longi- 
tudinal growth  of  the  radicle  drives  the  tip  deeper 
into  the  ground.  This  force,  combined  with  that 
due  to  transverse  growth,  gives  to  the  radicle  the 
power  of  a  wedge.  Even  a  growing  root  of  mod- 
erate size,  such  as  that  of  a  seedling  bean,  can 
displace  a  weight  of  some  pounds." 

The  radicle  is  constantly  growing  in  length, 
and  at  the  same  time  in  thickness.  Darwin  says,3 

1  p.  548.  2  p.  549.  3  p.  77. 


MOVEMENTS    OF    SEEDLINGS. 


39 


"  The  growing  part,  therefore,  does  not  act  like  a 
nail  when  hammered  into  a  board,  but  more  like 
a  wedge  of  wood,  which  whilst  slowly  driven  into 


FIG.  5.     SPLITTING  OF  A  ROCK  BY  THE  GROWTH  OF  THE  ROOT  OF  A  LARCH. 
("  Pflanzenleben.") 

a  crevice,  continually  expands  at  the  same  time  by 
the  absorption  of  water ;  and  a  wedge  thus  acting 
will  split  even  a  mass  of  rock"  (Fig.  5).1 

1  "  The  great  force  exerted  by  the  increase  in  size  of  the  stems  and 
roots  of  woody  plants  is  sometimes  demonstrated  in  an  extraordinary 


40  MOVEMENTS    OF    SEEDLINGS. 

Darwin  tried  many  experiments  to  ascertain 
how  the  movements  of  the  radicle  were  affected 
by  contact  with  external  objects.  Some  of  these 
experiments  consisted  in  affixing,  by  shellac,  or 
gum,  small  bits  of  card  to  one  side  of  the  tip  of 
the  radicle.  The  whole  growing  part  of  the  radi- 
cle bent  away  from  the  side  bearing  the  card,  or, 
when  card  was  placed  on  one  side  and  paper  on 
the  other,  the  radicle  bent  towards  the  thinner 
paper.  He  also  found  that  radicles  bent  toward 
moisture  and  away  from  light.  "  It  is  not  prob- 
able that  the  tip  when  buried  in  compact  earth 
can  actually  circumnutate,  and  thus  aid  its  down- 
ward passage,  but  the  circumnutating  movement 
will  facilitate  the  tip  entering  any  lateral  or 
oblique  fissure  in  the  earth,  or  a  burrow  made  by 
an  earthworm  or  larva ;  and  it  is  certain  that 
roots  often  run  down  the  old  burrows  of  worms. 
The  tip,  however,  in  endeavoring  to  circumnutate, 
will  continually  press  against  the  earth  on  all 
sides,  and  this  can  hardly  fail  to  be  of  the  highest 

manner  by  the  development  of  seedlings  in  crevices.  Thus,  at  the 
Marien  Cemetery,  in  Hanover,  Germany,  the  base  of  a  tree  has  dislodged 
the  stones  of  a  strongly  built  tomb.  One  of  the  stones,  which  measures 
23  by  28  by  56  inches  has  been  lifted  upon  one  side  to  the  height  of  five 
inches.  The  tree  measures  just  above  its  base  from  ten  to  fourteen  inches 
in  diameter."  "Physiological  Botany."  By  George  Lincoln  Goodale. 
Ivison,  Blakeman,  Taylor  &  Co. :  New  York  and  Chicago,  p.  395,  note  3. 


MOVEMENTS    OF    SEEDLINGS.  41 

importance  to  the  plant ;  for  we  have  seen  that 
when  little  bits  of  card-like  paper,  and  of  very 
thin  paper,  were  cemented  on  opposite  sides  of  the 
tip,  the  whole  growing  part  of  the  radicle  was 
excited  to  bend  away  from  the  side  bearing  the 
card,  or  more  resisting  substance,  towards  the  side 
bearing  the  thin  paper.1  We  may  therefore  feel 
almost  sure  that  when  the  tip  encounters  a  stone 
or  other  obstacle  in  the  ground,  or  even  earth 
more  compact  on  one  side  than  the  other,  the  root 
will  bend  away  as  much  as  it  can  from  the  obsta- 
cle or  the  more  resisting  earth,  and  will  thus  follow 
with  unerring  skill  a  line  of  least  resistance  .  .  ."  2 
(Fig.  6). 

1  "The  accompanying  figures  of  four  germinating  seeds  (Fig.  6) 
show,  firstly,  a  radicle  (A),  the  apex  of  which  has  become  so  much 
bent  away  from  the  attached  square  as  to  form  a  hook;  secondly  (B), 
a  hook  converted  through  the  continued  irritation  of  the  card,  aided 
perhaps  by  geotropism,  into  an  almost  complete  circle  or  loop.    The 
tip  in  the  act  of  forming  a  loop  generally  rubs  against  the  upper  part 
of  the  radicle,  and  pushes  off  the  attached  square ;  the  loop  then  con- 
tracts or  closes,  but  never  disappears,  and  the  apex  afterwards  grows 
vertically  downwards,  being  no  longer  irritated  by  any  attached  object. 
This  frequently  occurred,  and  is  represented  at  (C).  ...    In  another 
case,  shown  at  (D),  the  apex  in  making  a  second  turn  or  spire,  passed 
through  the  first  loop,  which  was  at  first  widely  open,  and  in  doing  so 
knocked  off  the  card;  it  then  grew  perpendicularly  downwards,  and 
thus  tied  itself  into  a  knot,  which  soon  became  tight."     "Power  of 
Movement   in   Plants,"   p.  178.     The  conclusions   drawn   from    these 
experiments  are  not  accepted  by  many  students,  and  the  experiments 
themselves  are  criticised,  as  containing  sources  of  error. 

2  p.  549. 


42 


MOVEMENTS    OF    SEEDLINGS. 


"After  a  radicle  has  been  deflected  by  some 
obstacle,  geotropism  directs  the  tip  again  to  grow 
perpendicularly  downwards ;  but  geotropism  is  a 


FIG.  6.     ZEA    MAYS.     Radicles  excited  to  bend   away  from   the    Little   Squares   of  Card 
attached  to  One  Side  of  their  Tips  (Darwin).     See  Note. 

feeble  power,  and  here,  as  Sachs  has  shown, 
another  interesting  adaptive  movement  comes  into 
play;  for  radicles  at  a  distance  of  a  few  milli- 
metres from  the  tip  are  sensitive  to  prolonged 


MOVEMENTS    OF    SEEDLINGS.  43 

contact  in  such  a  manner  that  they  bend  towards 
the  touching  object,  instead  of  from  it,  as  occurs 
when  an  object  touches  one  side  of  the  tip.  More- 
over, the  curvature  thus  caused  is  abrupt,  the 
pressed  part  alone  bending.  Even  slight  pressure 
suffices,  such  as  a  bit  of  card  cemented  to  one  side. 
Therefore  a  radicle,  as  it  passes  over  the  edge  of 
any  obstacle  in  the  ground,  will,  through  the  action 
of  geotropism,  press  against  it,  and  this  pressure 
will  cause  the  radicle  to  endeavor  to  bend  abruptly 
over  the  edge.  It  will  thus  recover  as  quickly  as 
possible  its  normal  downward  course. 

"  Radicles  are  also  sensitive  to  air  which  contains 
more  moisture  on  one  side  than  the  other,  and  they 
bend  towards  its  source.  It  is  therefore  probable 
that  they  are  in  like  manner  sensitive  to  dampness 
in  the  soil.  It  was  ascertained  in  several  cases 
that  this  sensitiveness  resides  in  the  tip,  which 
transmits  an  influence  causing  the  adjoining  upper 
part  to  bend  in  opposition  to  geotropism  towards 
the  moist  object.  We  may  therefore  infer  that 
roots  will  be  deflected  from  their  downward  course 
toward  any  source  of  moisture  in  the  soil. 

"  Again,  most  or  all  radicles  are  slightly  sensitive 
to  light,  and,  according  to  Wiesner,  generally  bend 
a  little  from  it.  Whether  this  can  be  of  any  ser- 


44  MOVEMENTS    OF    SEEDLINGS. 

vice  to  them  is  very  doubtful,  but  with  seeds  germi- 
nating on  the  surface  it  will  slightly  aid  geotropism 
in  directing  the  radicles  to  the  ground.  We  as- 
certained in  one  instance  that  such  sensitiveness 
resided  in  the  tip  and  caused  the  adjoining  parts 
to  bend  from  the  light.  .  .  .'u 

"  We  believe  that  there  is  no  structure  in  plants 
more  wonderful,  as  far  as  its  functions  are  con- 
cerned, than  the  tip  of  the  radicle.  If  the  tip  be 
lightly  pressed  or  burned  or  cut,  it  transmits  an 
influence  to  the  upper  adjoining  part,  causing  it  to 
bend  away  from  the  affected  side ;  and,  what  is 
more  surprising,  the  tip  can  distinguish  between  a 
slightly  harder  and  softer  object,  by  which  it  is 
simultaneously  pressed  on  opposite  sides.  If,  how- 
ever, the  radicle  is  pressed  by  a  similar  object  a 
little  above  the  tip,  the  pressed  part  does  not 
transmit  any  influence  to  the  more  distant  parts, 
but  bends  abruptly  towards  the  object.  If  the  tip 
perceives  the  air  to  be  moister  on  one  side  than  on 
the  other,  it  likewise  transmits  the  influence  to  the 
upper  adjoining  part,  which  bends  towards  the 
source  of  moisture.  When  the  tip  is  excited  by 
light  (though  in  the  case  of  radicles  this  was  as- 
certained in  only  a  single  instance)  the  adjoining 

1  pp.  551,  552. 


MOVEMENTS    OF    SEEDLINGS.  45 

part  bends  from  the  light;  but  when  excited  by 
gravitation  the  same  part  bends  towards  the  centre 
of  gravity.  In  almost  every  case  we  can  clearly 
perceive  the  final  purpose  or  advantage  of  the  sev- 
eral movements.  Two,  or  perhaps  more,  of  the 
exciting  causes  often  act  simultaneously  on  the  tip, 
and  one  conquers  the  other,  no  doubt  in  accordance 
with  its  importance  for  the  life  of  the  plant.  The 
course  pursued  by  the  radicle  in  penetrating  the 
ground  must  be  determined  by  the  tip;  hence  it 
has  acquired  such  diverse  kinds  of  sensitiveness. 
It  is  hardly  an  exaggeration  to  say  that  the  tip  of 
the  radicle,  thus  endowed,  and  having  the  power 
to  direct  the  movements  of  the  adjoining  parts, 
acts  like  the  brain  of  one  of  the  lower  animals ; 
the  brain  being  seated  within  the  anterior  end  of 
the  body,  receiving  impressions  from  the  sense- 
organs,  and  directing  the  several  movements." l 

In  seedlings,  such  as  the  Bean  (Fig.  8),  and 
Squash  (Fig.  9),  which  lift  their  cotyledons  above 
the  ground,  the  stem  below  the  cotyledons,  called 
by  Darwin  the  hypocotyl,  is  the  first  to  break  out 
from  the  seed-coats  after  the  protrusion  of  the  rad- 
icle. In  seedlings,  such  as  the  Pea,  where  the 

1  p.  572.  This  is  cojisjtfered  aji  extravagant  .assumption  by  Sachs 
.9,nd  others. 


46 


MOVEMENTS    OF    SEEDLINGS. 


8 


FIG.  7.     GERMINATION    OF   PEA.        FIG.  8.     GERMINATION    OF    BEAN. 


MOVEMENTS    OF    SEEDLINGS. 


47 


cotyledons  remain  buried  (Fig.  7),  the  stem  above 
cotyledons,  the  epicotyl,  breaks  forth.  These  or- 
gans are  generally  arched  at  first ;  this  form  prob- 


FIG.  9.     GERMINATION    OF   SQUASH   (Cucurbita  Pepo). 

ably  saves  the  tender,  growing  apex  from  being 
rubbed. 

"  As  the  arch  grows  upwards,  the  cotyledons 
are  dragged  out  of  the  ground.  The  seed-coats 
are  either  left  behind  buried,  or  are  retained  for  a 
time,  still  enclosing  the  cotyledons.  These  are 


48  MOVEMENTS    OF    SEEDLINGS. 

afterwards  cast  off  merely  by  the  swelling  of  the 
cotyledons.  .  .  .  The  cotyledons  can  now  assume 
the  function  of  leaves  and  decompose  carbonic 
acid ;  they  also  yield  up  to  other  parts  of  the  plant 
the  nutriment  they  often  contain.  When  they 
contain  a  large  stock  of  nutriment,  they  generally 
remain  buried  beneath  the  ground,  owing  to  the 
small  development  of  the  hypocotyl ;  and  thus 
they  have  a  better  chance  of  escaping  destruction 
by  animals.  ..." 

"  Our  seedling  now  throws  up  a  stem  bearing 
leaves,  and  often  branches,  all  of  which  whilst 
young  are  continually  circumnutating.  If  we  look, 
for  instance,  at  a  great  acacia  tree,  we  may  feel 
assured  that  every  one  of  the  innumerable  growing 
shoots  is  constantly  describing  small  ellipses ;  as  is 
each  petiole,  sub-petiole,  and  leaflet.  The  latter, 
as  well  as  ordinary  leaves,  generally  move  up  and 
down  in  nearly  the  same  vertical  plane,  so  that 
they  describe  very  narrow  ellipses.  The  flower- 
peduncles  are  likewise  continually  circumnutating. 
If  we  could  look  beneath  the  ground,  and  our  eyes 
had  the  power  of  a  microscope,  we  should  see  the 
tip  of  eacli  rootlet  endeavoring  to  sweep  small 
ellipses  or  circles  as  far  as  the  pressure  of  the  sur- 

i  p.  556. 


MOVEMENTS    OP    SEEDLINGS.  49 

rounding  earth  permitted.  All  this  astonishing 
amount  of  movement  has  been  going  on  year  after 
year  since  the  time  when,  as  a  seedling,  the  tree 
first  emerged  from  the  ground."  1 

1  p.  558. 


50  THE    BIRTH    OF    PICCIOLA. 


V. 

THE    BIRTH    OF   PICCIOLA.1 

ONE  day,  at  the  usual  hour,  De  Charney  was 
walking  in  the  courtyard  of  his  prison,  his  eyes 
cast  down,  his  arms  crossed  behind  him.  He  was 
pacing  slowly  step  by  step,  as  if  thus  he  could 
enlarge  the  narrow  space  permitted  to  him. 

Spring  was  approaching ;  he  breathed  a  sweeter 
air,  and  to  be  free,  master  of  the  earth  and  of 
space,  seemed  to  him  an  object  of  desire. 

He  counted  one  by  one  the  stones  of  the  little 
courtyard,  perhaps  to  verify  former  calculations, 
for  it  was  not  the  first  time  that  he  had  numbered 
them,  when  he  saw  at  his  feet  a  small  mound  of 
earth,  slightly  cleft  at  the  summit,  thrown  up 
between  two  paving-stones.  He  stooped,  and  his 
heart  beat  quickly,  without  his  knowing  why. 
Everything  is  an  object  of  hope  or  fear  to  the 

1  Translated  from  the  French  of  Joseph  Xavier  Saintine.  "  Picciola," 
Chap.  III.  Picciola  (signifying  "  dear  little  one  ")  is  the  name  given 
by  Count  de  Cliarney,  a  political  prisoner  of  Napoleon  in  the  fortress 
of  Fenestrella,  to  a  plant  which  had  sown  itself  in  the  courtyard  of  his 
prison. 


THE    BIRTH    OF    PICCIOLA.  51 

captive ;  for  the  most  insignificant  events  he  seeks 
some  important  cause  which  may  bring  about  his 
deliverance.  Perhaps  this  slight  disturbance  at 
the  surface  is  produced  by  some  great  work  below. 
There  may  be  passages  beneath  the  earth  which 
will  open  and  admit  him  to  the  fields  and  moun- 
tains. Perhaps  his  former  friends  and  confederates 
are  digging  a  mine  in  order  to  reach  him  and  bring 
him  back  to  life  and  liberty. 

He  listens  attentively  and  thinks  he  hears  a 
dull,  prolonged  sound  from  the  interior  of  the  for- 
tress ;  he  raises  his  head,  and  the  breeze  brings  him 
the  rapid  clang  of  the  tocsin.  The  rolling  of  drums 
is  repeated  like  a  signal  of  war  along  the  ramparts. 
He  trembles  and  brushes  the  sweat  convulsively 
from  his  forehead.  Will  he  soon  be  free  ?  Has 
France  changed  her  master  ? 

The  dream  vanishes ;  reflection  destroys  the 
illusion.  Confederates  he  has  no  longer,  and 
friends  he  never  possessed.  He  listens  again.  The 
same  noises  strike  his  ear,  but  they  bring  far  other 
thoughts.  This  clang  of  the  tocsin,  this  rolling  of 
the  drum,  are  only  the  accustomed  striking  of  a 
clock,  and  the  usual  call  which  summons  the  sol- 
diers of  the  citadel  to  their  daily  drill. 

De  Charney  smiled  bitterly  and  pitied  himself 


52  THE    BIRTH    OF    PICCIOLA. 

to  think  that  a  tiny  animal,  a  mole  that  had  lost 
its  way,  a  field-mouse  scratching  up  the  earth 
beneath  his  feet,  had  made  him  believe  for  an 
instant  in  the  fidelity  of  men  and  the  overthrow 
of  a  great  empire. 

He  wished  to  satisfy  himself,  however,  and  bend- 
ing down,  he  pushed  away  the  earth  on  either  side 
of  the  cleft  hillock.  He  saw  then  with  astonish- 
ment that  his  foolish  emotion  had  been  caused  not 
even  by  a  sentient  being,  armed  with  claws  and 
teeth,  but  by  a  feeble  plant,  hardly  able  to  germi- 
nate, pale  and  languishing.  Profoundly  humiliated, 
he  rose  and  was  about  to  crush  it  under  his  heel, 
when  a  fresh  breeze,  laden  with  the  odor  of  honey- 
suckle and  of  syringa,  blew  across  his  face  as  if  to 
ask  mercy  for  the  poor  plant,  which  perhaps  some 
day  would  also  be  able  to  offer  him  perfumes. 

An  idea  struck  him  which  arrested  his  movement 
of  disgust. 

How  had  this  tender  herb,  so  fragile  that  it 
might  be  broken  at  a  touch,  been  able  to  pierce 
the  dry,  sun-hardened  earth,  trodden  by  his  foot- 
steps, and  almost  cemented  to  the  granite  flags. 
He  bent  again  and  examined  the  plant  with  more 
attention. 

He  saw  at  its  upper  extremity  a  sort  of  double 


THE    BIRTH    OF    PICCIOLA.  53 

fleshy  valve,  which,  embracing  its  first  leaves,  pre- 
served them  from  the  attacks  of  enemies,  and  gave 
them  the  means  of  breaking  through  the  hard 
crust  of  earth  to  seek  the  air  and  the  sun. 

"Ah,"  he  said,  "there  is  the  whole  secret.  Na- 
ture has  given  it  this  strength,  like  the  little 
chickens,  which,  before  they  are  hatched  are  al- 
ready armed  with  a  beak  strong  enough  to  break 
the  shell  in  which  they  are  enclosed.  Poor  pris- 
oner !  at  least  you  possess  in  your  captivity  instru- 
ments which  will  aid  you  to  become  free." 

He  looked  at  the  plant  and  no  longer  thought 
of  destroying  it. 

The  next  day,  in  his  usual  promenade,  walking 
with*  long  strides  and  absorbed  in  his  own  thoughts, 
he  almost  stepped  upon  it  and  stopped  short. 
Surprised  by  the  interest  which  his  new  acquaint- 
ance inspired  in  him,  he  noted  its  progress. 

The  plant  had  grown,  and  under  the  rays  of  the 
sun  had  nearly  lost  the  sickly  pallor  of  the  previous 
day.  He  reflected  on  the  power  of  this  weak, 
blanched  stem  to  absorb  the  light,  to  nourish  itself, 
to  strengthen  itself,  and  to  borrow  from  the  prism 
the  colors  which  it  needed,  colors  foreordained  for 
every  one  of  its  parts. 

Its  leaves,  he  thought,  will  doubtless  be  tinted 


54  THE    BIETH    OF    PICCIOLA. 

with  a  different  shade  from  its  stem,  and  of  what 
color  will  the  flowers  be?  Yellow,  blue,  red? 
Why,  since  they  are  fed  by  the  same  juice  as  the 
stem  and  leaves,  do  they  not  clothe  themselves  in 
the  same  livery  ?  How  can  they  find  azure  and 
scarlet  where  the  others  find  only  a  bright  or  dark 
green  ?  It  will  be  so,  however ;  for,  in  spite  of  the 
disorder  and  confusion  of  the  world,  matter  follows 
its  fixed,  though  blind  march.  "  Very  blind,"  he  re- 
peated. "  To  prove  it  I  should  only  need  to  see  that 
the  two  fleshy  lobes  which  have  aided  the  plant  to 
leave  the  earth,  but  are  now  useless  to  its  life,  are 
still  nourished  by  its  substance,  and,  hanging  down, 
weary  it  with  their  weight.  Of  what  use  are  they 
now  ?  "  As  he  spoke,  night  was  approaching,  —  a 
wintry  spring  night.  The  two  lobes  rose  slowly, 
under  his  very  eyes,  and  as  if  wishing  to  justify 
themselves  against  his  blame,  approached  each 
other  arid  enclosed  in  their  bosom  the  tender,  frag- 
ile leaves,  which  the  sun  was  leaving,  and  which, 
thus  sheltered  and  warmed,  slept  beneath  the  pro- 
tecting wings  that  the  plant  folded  over  them.1 

1  This  is  perhaps  the  first  allusion  to  the  sleep  of  cotyledons.  "Pic- 
ciola"  was  published  in  1856.  Darwin,  in  "  The  Power  of  Movements  in 
Plants,"  published  in  1880,  investigates  the  subject,  and  concludes  thus  : 
"  Reflecting  on  these  facts,  our  conclusion  seems  justified,  that  the 
nyctitropic  movements  of  cotyledons,  by  which  the  blade  is  made  to 


THE    BIRTH    OF    PICCIOLA.  55 

The  philosopher  understood  still  better  this  mute 
but  decisive  answer,  because  the  outer  surfaces  of 
the  vegetable  bivalve  had  been  attacked  and  bitten 
the  night  before  by  little  snails,  whose  silvery 
traces  were  still  visible. 

This  strange  discussion,  thoughts  on  one  side 
and  action  on  the  other,  between  the  man  and  the 
plant,  could  not  rest  there.  De  Charney  was  too 
familiar  with  metaphysics  to  be  vanquished,  so 
readily  by  a  good  argument. 

"  Very  well,"  he  replied ;  "  here,  as  elsewhere,  a 
happy  combination  of  circumstances  has  favored 
this  weak  being.  To  be  armed  with  a  lever  to 
raise  the  soil,  and  a  buckler  to  protect  its  tender 
head,  is  a  twofold  condition  of  its  existence.  If 
this  had  not  been  fulfilled,  the  plant  would  have 
perished  in  its  germ,  like  myriads  of  others  of  its 
kind,  that  Nature  has  doubtless  created  imperfect, 
unfinished,  unable  to  live  and  grow.  How  can  one 
guess  how  many  false  and  impotent  combinations 
she  has  tried  before  bearing  a  single  being  fitted 
to  live?  For  thousands  of  centuries  matter  has 

stand  either  vertically,  or  almost  vertically,  upwards  or  downwards  at 
night,  has  been  acquired,  at  least  in  most  cases,  for  a  special  purpose: 
nor  can  we  doubt  that  this  purpose  is  the  protection  of  the  upper  sur- 
face of  the  blade,  and  perhaps  of  the  central  bud  or  plumule,  from 
radiation  at  night." 


56  THE    BIRTH    OF    PICCIOLA. 

been  torn  by  alternate  attraction  and  repulsion. 
Is  it  then  surprising  that  chance  has  sometimes  hit 
the  mark  ?  This  covering  may  protect  the  first 
leaves,  —  I  grant  it ;  but  will  it  increase,  will  it 
shelter  the  other  leaves  against  the  cold  and  the 
attacks  of  insects  ?  No.  The  next  spring,  when 
another  foliage  will  be  born,  fragile  as  this,  will  it 
be  here  to  protect  that  ?  No.  Nothing  here  has 
been  foreseen,  nothing  is  the  fruit  of  intelligent 
thought,  but  only  of  a  lucky  chance." 

Ah,  Count  de  Charney,  nature  holds  more  than 
one  answer  to  refute  your  arguments.  Wait,  and 
see  in  this  weak  and  solitary  plant,  brought  to  you 
in  the  dulness  of  your  prison,  a  beneficent  thought 
of  Providence  rather  than  a  stroke  of  chance. 
These  excrescences,  in  which  you  yourself  have 
divined  a  lever  and  a  shield,  have  already  rendered 
other  services  to  this  feeble  plant.  After  having 
served  it  through  the  winter  as  a  covering  in  the 
cold  soil,  when  the  right  time  arrived  they  lent  it 
their  nourishing  breasts,  they  fed  the  simple  germ 
when  it  had  neither  roots  to  draw  the  moisture 
from  the  earth,  nor  leaves  to  breathe  the  air  and 
the  sun.  You  are  right,  Count  de  Charney  ;  these 
protecting  wings  which  now  cover  the  young  plant 
£0  maternally  will  not  develop  with  her ;  they  will 


THE    BIRTH    OF    PICCIOLA.  57 

fall,  but  after  having  finished  their  task  and  when 
their  charge  has  acquired  the  strength  to  do  with- 
out them.  Do  not  trouble  yourself  about  the 
future.  Nature  watches  over  this  plant,  as  over 
her  sisters,  and  while  the  northern  winds  bring 
the  snow  and  hail  from  the  Alps,  the  new  leaves, 
still  in  the  bud,  will  find  there  a  sure  refuge,  an 
asylum  made  especially  for  them,  closed  from  the 
air,  covered  with  gum  and  resin,  that  expands 
according  to  their  needs,  and  opens  only  at  the 
right  time,  under  a  favorable  sky.  They  will  issue 
clad  in  warm  furs,  silky  garments  of  down  that 
will  defend  them  from  the  late  frosts  and  atmos- 
pheric caprices.  Has  ever  a  mother  watched  more 
carefully  the  welfare  of  her  children  ? 

The  philosopher  had  followed  attentively  the 
progress  and  transformations  of  the  plant.  Again 
and  again  he  had  argued  with  her,  and  for  every 
argument  she  had  her  answer. 

"  Of  what  use  are  these  stiff  hairs  that  clothe 
your  stem  ?  "  he  asked  her. 

And  the  next  day  she  showed  them  to  him  cov- 
ered with  a  light  frost,  which,  held  thus  at  a  dis- 
tance, had  not  been  able  to  freeze  the  tender  bark. 

"  Of  what  use  in  fine  weather  will  be  your  warm 
covering  of  wool  and  down.?" 


58  THE    BIRTH    OF    PICCIOLA. 

The  fine  weather  came,  and  the  plant  took  off 
her  winter  mantle  to  put  on  her  spring  garment  of 
green,  and  her  new  branches  were  without  these 
silky  coverings,  henceforth  useless. 

"  But  if  the  storm  rage,  the  wind  will  break  you, 
and  the  hail  will  tear  your  leaves,  too  tender  to 
resist." 

The  wind  blew,  and  the  young  plant,  too  weak 
to  resist,  bent  to  the  earth,  defending  itself  by 
yielding.  The  hail  came,  and  by  a  new  manoeuvre, 
the  leaves,  ranging  themselves  along  the  stem  and 
pressing  one  against  the  other  for  mutual  protec- 
tion, offered  their  solid  ribs  to  the  weight  of  the 
missiles.  Union  gave  them  strength,  and  this  time, 
as  before,  the  plant  came  out  of  the  combat,  not 
without  some  light  wounds,  but  living,  strong,  and 
ready  to  expand  under  the  rays  of  the  sun,  which 
was  already  healing  its  injuries. 

"Is  chance,  then,  intelligent?"  cried  De  Charney. 
"  Must  we  spiritualize  matter  or  materialize  spirit  ?  " 
And  he  did  not  cease  to  interrogate  his  mute  in- 
terlocutor. He  loved  to  see  her  grow,  to  follow 
her  in  her  gradual  changes. 

One  day,  after  he  had  long  contemplated  her,  he 
fell  into  a  reverie  by  her  side,  and  his  thoughts  had 
an  unusual  sweetness.  Walking  up  and  down  the 


THE    BIRTH    OF    PICCIOLA.  59 

court,  he  felt  calm  and  happy  in  them.  Then, 
raising  his  head,  he  saw  at  the  grated  window  the 
flycatcher,  who  seemed  to  be  observing  him.  He 
blushed  at  first  as  if  the  other  had  guessed  his 
thoughts,  and  then  smiled,  for  he  despised  his 
neighbor  no  longer.  Had  he  the  right  to  do  so  ? 
Was  not  his  spirit,  also,  absorbed  in  the  study  of 
one  of  the  lowest  works  of  nature  ? 

"Who  knows,"  he  cried  to  himself,  "if  this 
Italian  has  not  found  as  many  wonders  in  a  fly  as 
I  have  discovered  in  my  plant  ?  " 

Entering  his  cell,  the  first  thing  which  caught  his 
eye  was  this  fatalistic  sentence,  written  by  himself 
upon  the  wall  two  months  before  :  Chance  is  blind 
and  is  the  sole  author  of  creation. 

He  took  a  bit  of  charcoal  arid  wrote  beneath  the 
words,  perhaps. 


60  ROOT   AND    CKOWN. 


VI. 

ROOT   AND   CROWN.1 
THE    GUIDING    OF    RAINWATER    TO    THE     ROOTLETS. 

ANY  ONE  who  has  been  overtaken  by  a  sudden 
storm,  and  has  taken  refuge  under  the  branches  of 
a  tree,  will  remember  that  the  leafy  roof  above 
him  afforded  him  shelter  for  a  time,  and  that  the 
ground  under  the  tree  did  not  become  wet.  A 
part  of  the  rain,  to  be  sure,  runs  down  the  tree 
trunk,  and  in  many  kinds  of  trees,  as,  for  instance, 
the  Yew  and  the  Plane,  this  quantity  is  not  insig- 
nificant ;  but  in  most  trees,  the  rainwater  that  thus 
reaches  the  earth  quickly  disappears,  and  is  hardly 
to  be  compared  with  the  amount  that  pours  from 
the  circumference  of  the  leafy  crown  of  the  tree. 
This  effect  is  brought  about  by  the  position  of  the 
surfaces  of  the  leaves.  In  almost  all  our  deciduous 
trees,  in  the  Linden  and  Birch,  Pear  and  Apple, 
Plane  and  Maple,  Ash  and  Horse-chestnut,  Poplar 
and  Alder,  the  leaves  of  the  crown  slope  outwards 

1  Freely  translated  from  the  German  of  Dr.  A.  Kerner  von  Mari- 
laun.  "  Pflanzenleben."  Leipzig,  1888.  Vol.  I.  p.  85. 


ROOT    AND    CROWN.  61 

and  lap  over  each  other,  so  that  the  rain  which 
strikes  on  any  one  of  the  upper  leaves  of  the  tree 
runs  down  to  the  apex  of  the  leaf,  where  it  collects 
in  the  form  of  a  drop,  and  falls  on  the  shelving 
surface  of  a  leaf  below.  There  it  unites  with 
freshly  fallen  water,  and  so  descends  from  step  to 
step,  drawing  ever  nearer  to  the  edge  of  the  tree, 
till  it  finally  shows  itself  in  a  number  of  little 
cascades  on  every  side. 

From  the  lower,  outer  leaves  of  the  whole  crown 
the  water  falls  on  the  earth,  and  the  dry  ground 
under  the  tree  is  enclosed  after  every  rain  by  a 
zone  of  thoroughly  wet  soil.  If  we  dig  in  these 
wet  places,  we  find  that  the  young  roots  with  their 
absorbing  fibrils  have  penetrated  just  as  far  as  this 
wet  zone.  In  young  trees,  where  the  rootlets  are 
near  the  tree  trunk,  the  crown  is  less  spreading 
and  the  wet  zone  is  of  correspondingly  small  cir- 
cumference. But  as  the  reach  of  the  drip  widens, 
the  roots,  seeking  moisture,  also  extend,  and  roots 
and  leaves  actually  keep  step  in  their  outward 
growth.  It  seems  to  me  probable  that  the  gar- 
dener's custom  of  pruning  the  branches  and  roots 
of  the  trees  which  he  transplants  is  for  the  purpose 
of  bringing  them  into  accordance  with  this  law. 
Practically,  the  gardener  or  farmer  always  observes 


62  ROOT   AND    CROWN. 

the  rule  that  the  branches  of  the  root  and  the 
branches  of  the  crown  shall  be  equally  shortened, 
so  that  the  forming  roots  shall  be  directly  under 
the  drip  of  the  forming  crown. 

There  is  also  a  similar  way  of  carrying  off  the 
water  to  be  observed  in  the  Evergreens.  Let  us 
look  at  the  common  Pine.1  The  branches  start 
nearly  at  right  angles  with  the  trunk,  run  out 
horizontally  for  some  distance,  and  then  curve 
upwards  in  the  form  of  a  bow.  The  needles  near 
the  end  of  every  branch  point  upwards,  while  those 
a  little  further  from  the  end,  where  the  branch  is 
almost  horizontal,  are  directed  obliquely  down- 
wards and  outwards.  The  raindrops  which  strike 
the  upraised  needles  run  down  along  them  to  the 
bark  of  the  branch,  and  thence  to  other  needles 
with  their  points  directed  downwards  and  out- 
wards. On  the  ends  of  these  needles  great  drops 
are  gradually  formed,  which  finally  drop  off  and 
fall  on  the  upraised  needles  of  a  lower  branch. 
Guided  in  this  manner,  the  rainwater  is  brought 
ever  lower  and  lower,  and  at  the  same  time  towards 
the  exterior  of  the  tree. 

So  it  is  with  the  Larch.  The  raindrops  which 
fall  on  the  bushy  young  sprouts  collect  and  come 

1  The  common  Pine  in  Germany  is  the  Scotch  Pine  (Pinus  sylvestris). 


ROOT    AND    CEOWN.  63 

gradually  to  the  long,  pendent  shoots  of  the  lower 
branches,  where  great  drops  are  always  to  be  seen 
on  the  ends  pointed  to  the  ground.  These  drops 
finally  make  a  stream  which  falls  on  the  earth. 
The  long,  pendent  shoots  of  the  Larch  droop  from 
the  outmost  point  of  every  branch,  and  the  tree  is 
in  the  form  of  a  pyramid,  so  that  nearly  all  the 
water  that  falls  upon  the  tree  reaches  the  long 
shoots  that  hang  down  from  the  lowest,  most 
extended  branches.  Although  the  Larch,  with  its 
tender  needles,  does  not  seem  as  if  it  would  afford 
shelter  from  the  rain,  nevertheless,  the  ground 
under  it  remains  dry,  and  most  of  the  rainwater 
falling  on  it  is  brought  to  the  circumference  of  the 
tree.  In  fact,  it  is  one  of  those  trees  where  very 
little  water  runs  down  the  main  stem ;  almost  all 
the  rain  which  reaches  it  is  guided  to  the  rootlets 
at  a  certain  distance  from  the  trunk. 

Many  shrubs  and  perennial  herbs  also  guide  the 
rainwater  to  that  part  of  the  soil  in  which  the 
rootlets  are  embedded,  or,  to  be  more  precise,  the 
roots,  with  their  delicate  fibrils,  grow  in  the  direc- 
tion where  the  drip  from  the  leaves  moistens  the 
ground.  Some  members  of  the  Arum  family  are 
especially  striking  in  this  respect.  Fig.  10  repre- 
sents a  Caladium.  If  one  of  these  plants,  which  has 


64  KOOT    AND    CKOWN. 

been  cultivated  in  open  ground,  be  dug  up,  the 
ends  of  the  roots,  which  run  out  horizontally  from 
the  stubby  rootstock,  will  be  found  embedded  di- 
rectly under  the  points  of  the  large  leaves. 

It  must  not  remain  unnoticed  that  the  petioles 
of  leaves  which  lead  the  rainwater  centrifugally, 
as  the  leaves  of  Horse-chestnut  and  Maple,  of  shrubs 
like  the  Lilac,  and  of  climbing  plants  like  the  Tro- 
paeolum,1  are  not  channelled  on  the  upper  side,  but 
are  round  and  smooth.  If  a  sloping  leaf  shows  a 
system  of  channels  for  the  water,  these  channels 
run  along  the  veins  and  end  at  the  apex  of  the 
leaves,  or  at  the  points  of  the  lobes.  There  the 
water  collects  in  the  form  of  drops,  and  must  fall 
on  the  leaves  which  make  the  succeeding  lower 
and  outer  steps. 

In  striking  contrast  to  these  plants,  with  leaves 
sloping  outwards  and  roots  spreading  horizontally, 
are  those  with  bulbs  or  short  rootstocks  and  de- 
scending rootlets.  This  contrast  in  the  growth  of 
the  root  is  shown  in  Fig.  10,  1  and  2.  Above  the 
ground  it  is  foretold  by  the  form  and  position  of  the 
leaves  on  which  the  rainwater  strikes.  In  all  these 
plants  the  leaf  surfaces  slope  towards  the  axis. 

1  When  several  examples  of  plants,  illustrating  a  single  point,  are 
given,  the  liberty  has  been  taken  of  choosing  those  only  which  are  well- 
known  in  America.  —  ED. 


KOOT    AND    CROWN.  65 

They  are  also  concave  on  their  upper  side,  and 
often  show  a  system  of  channels  which  guides  the 
water  to  the  stem,  and  thence  to  the  tap-root  and 
short  absorbing  rootlets.  The  leaves  of  bulbous 


FIG.  10.     CENTRIFUGAL  AND   CENTRIPETAL   CONDUCTING   OF   WATER. 
I.   In  a  Caladium.      2.   In  a  Rhubarb  Plant.      ("  Pflanzenleben,") 

plants,  like  those  of  the  Hyacinth  and  Tulip,  all 
slope  inward  and  are  concave  on  the  upper  side, 
and  often  excavated  into  deep  channels.  Through 
these  channels  the  rainwater  runs,  and  so  reaches 
that  part  of  the  earth  where  the  bulb  with  its 


66  EOOT    AND    CKOWN. 

mass  of  rootlets  is  embedded.  In  plants  with  root- 
stocks,  if  the  leaves  are  in  a  rosette  and  the  rosette 
lies  on  the  ground,  as  with  the  Dandelion,  Plantain, 
etc.,  a  channel  or  several  main  channels  are  to  be 
found  on  the  upper  side  of  the  leaf,  and  the  leaves 
are  always  so  arranged  that  the  rainwater,  falling 
on  the  rosette,  must  flow  towards  the  centre,  from 
which  the  root  runs  perpendicularly  downwards. 
If  plants  which  guide  the  rainwater  centripetally 
have  petioled  leaves,  they  have  also  a  distinct  chan- 
nel on  the  upper  side  of  the  leaf-stalk,  which  is 
often  deepened  by  the  growth  of  a  green  border, 
or  sometimes  a  dry  border,  on  both  edges.  The 
channels  on  the  stems  of  the  radical  leaves  of 
Rhubarb  (Fig.  10),  Beet,  Peony,  and  most  Violets 
are  especially  interesting. 

The  arrangements  of  plants  with  caul  in  e  leaves 
for  carrying  off  the  water  are  much  more  compli- 
cated. When  leaves  on  a  stem  high  above  the 
ground  catch  rainwater,  as  the  Rhubarb  does,  they 
can  keep  their  position  better  if  their  bases  are 
joined  directly  to  the  stem,  or  clasp  it.  If  such 
leaves  were  placed  on  long,  upright  stalks,  they 
would  require  an  immense  bulwark  of  supporting 
cells,  and,  therefore,  they  are  rarely  petioled. 
Among  well-known  plants  we  can  only  name  some 


ROOT    AND    CROWN.  67 

Pelargoniums  (as  P.  zonale,  House-Geranium).  In 
most  cases  cauline  leaves  which  lead  the  water 
centripetally  are  either  sessile  or  short-stalked,  and 
often  clasp  the  stem  with  lobes  or  auricles. 

If  the  leaves  are  opposite  and  decussating,  the 
water  is  usually  carried  down  in  two  channels, 
which  run  along  the  stem  from  one  pair  of  leaves 
to  the  next.  .  .  . 

When  the  leaves  are  not  opposite,  but  are  ar- 
ranged in  a  spiral,  the  water  filters  down  the  spiral 
from  leaf  to  leaf.  Many  Thistles  show  this  flowing 
off  of  the  water  along  a  spiral  line  very  beautifully. 
With  little  grains  of  shot  we  may  imitate  the 
action  of  the  raindrops,  and  by  this  means  see  very 
plainly,  in  plants  with  firm  leaves,  the  path  natu- 
rally taken  by  the  falling  drops.  Such  grains  of 
shot  dropped  upon  a  growing  plant  of  Alfredia 
(Fig.  II),1  will  roll  down  over  the  concave  surface 
of  the  upper  leaf,  and  strike  the  stem  which  the 
leaf  clasps.  Then,  rolling  over  a  lobe  of  the  base 
of  the  leaf,  it  will  fall  on  the  middle  of  the  surface 
of  the  leaf  below,  because  the  clasping  auricles  of 
each  leaf  lie  over  the  middle  of  the  next  lower 
leaves.  Thence  the  grains  of  shot  fall  on  the  third 
leaf,  and  so  on,  till  they  reach  the  earth  close  to 

1  The  Alfredia  is  a  kind  of  thistle  (Carduus  cernuus). 


BOOT   AND    CKOWK. 


the   stem.      The   raindrops   naturally   follow  the 
same  path  as  the  shot,  but  in  their  case  not  only 


FIG.  II.     GUIDING   OF  THE   RAINWATER. 
I.  In  the  Alfredia  (I).     2.   In  the  Mullein  (Verbascum  phlomoides).     ("  Pflanzenleben.") 

the  first  leaf,  but  every  leaf,  is  covered  with  drops, 
and  thus  the  stream,  flowing  from  leaf  to  leaf,  is 


ROOT    AND    CROWN.  69 

continually  reinforced   and   becomes   greater  and 
greater.   .  .  . 

A  slightly  different  method  of  guiding  the  rain- 
water may  be  seen  in  the  Mullein  (Fig.  II).1  The 
upper  leaves,  half  clasping  the  stem,  are  upright, 
like  those  of  the  Alfredia^  and  guide  the  water 
downward  in  the  same  way.  But  the  leaves  in 
the  middle  portion  of  the  stem  are  only  upright 
for  two- thirds  of  their  length.  The  upper  third  is 
recurved,  and  the  rain  which  falls  on  this  upper 
third  drops  from  the  points  of  the  leaves,  and 
would  thus  seem  to  run  off  centrifugally.  But  the 
shape  of  the  plant  is  a  slender  pyramid,  as  the 
leaves  grow  continually  smaller  towards  the  top  of 
the  stem,  and  the  water  drops  from  the  apex  of 
one  leaf  to  the  portion  of  the  next  lower  leaf  which 
slopes  inward,  and  thus  leads  the  water  centrip- 
etally.  In  this  way,  the  whole  of  the  rainwater 
falling  on  such  a  plant  finally  reaches  the  neighbor- 
hood of  the  tap-root,  and  is  used  to  the  best  ad- 
vantage by  the  rootlets  proceeding  from  it.  ... 

1  Our  species  of  Mullein,  Veibascum  thapsus,  carries  off  the  rain- 
water in  the  same  manner.  An  experimenter  has  told  me  that  it  is 
necessary  to  cultivate  plants  by  themselves  in  order  to  see  this  relation 
in  the  position  of  leaves  and  rootlets,  for  in  the  woods  and  fields  so 
many  conditions  enter  into  the  result  that  the  growth  of  the  roots  may 
be  determined  by  other  causes.  —  ED. 


70  ROOT    AND    CROWN. 

The  guiding  of  the  water  to  the  rootlets  is  of 
the  greatest  importance,  for  the  water  is  not  only 
absorbed  by  them,  but  is  carried,  as  we  shall  see 
later,  over  the  whole  plant.  .  .  . 

In  the  building  up  of  the  molecules  of  sugar,  of 
starch,  of  cellulose,  and  of  all  important  substances 
out  of  which  the  plant  is  formed,  the  atoms  of 
water  are  used  as  building  stones,  and  without 
water  no  growth  could  take  place.  From  this 
point  of  view  water  must  be  regarded  as  an  indis- 
pensable foodstuff  of  plants,  no  less  than  the  car- 
bonic acid  of  the  air.  Water,  however,  plays 
another  weighty  part  in  the  life  of  the  plant.  The 
mineral  salts  which  nourish  water-plants,  earth- 
plants,  and  air-plants,  as  well  as  the  organized  food 
on  which  parasitic  plants  feed,  can  be  taken  up 
only  in  solutions.  The  salts  can  pass  through  the 
cells  only  when  their  walls  are  saturated  with 
water,  and  must  be  dissolved  in  water  in  order  to 
be  brought  into  the  interior  of  the  plant  wherever 
they  are  needed.  Water  acting  in  this  capacity  in 
living  plants  is  to  be  regarded  as  the  motive  power. 
As  the  mill  by  the  brook  works  only  when  its 
wheels  are  put  in  motion  by  the  water,  so  the 
living,  growing  plant  demands  a  great  quantity  of 
available  water  in  order  that  its  complicated  life 


ROOT    AND    CKOWN.  71 

processes  may  be  carried  on.  This  water  will  not 
be  chemically  bound,  like  that  which  is  used  in 
food,  and  will  not  long  be  retained.  We  must  con- 
ceive that  water  is  continually  streaming  through 
the  living  plant.  In  the  course  of  a  summer,  an 
amount  of  water  passes  through  the  plant  which 
many  times  exceeds  its  weight.  The  water  which 
is  chemically  united  with  the  organic  compounds 
of  the  plant,  is  extremely  slight  in  comparison 
with  that  used  in  carrying  its  food  materials.  .  .  . 
It  is  therefore  plain,  as  water  is  a  necessary 
food,  and  is  needful  in  transporting  other  food 
materials,  that  a  sufficient  supply  is  indispensable 
to  the  life  of  the  plant.1 

1  "  Pflanzenleben,"  I.  pp.  199,  200. 


72  TKEES    IX    WLNTEK. 


VII. 

TREES   JN    WINTER. 

IN  Northern  America  we  rejoice  in  a  yearly 
spectacle  which  exceeds  in  richness  and  variety 
of  color  any  other  forest  scene  in  the  world.  As 
September  advances,  the  Swamp  Maples  and  Su- 
machs clothe  themselves  in  flaming  red ;  then  the 
Elms,  Birches,  Chestnuts,  and,  later,  the  Beeches, 
imitate  the  sunshine ;  lastly,  the  Oaks  turn  with 
a  variety  of  rich,  deep  hues,  which  are  the  most 
beautiful  and  satisfying  of  all.  The  reason  of 
this  brilliancy  of  coloring,  so  much  more  strik- 
ing than  the  woods  of  Europe,  is  not  understood, 
although  it  is  often  attributed  to  the  greater 
dryness  of  the  climate. 

It  is  a  common  mistake  to  suppose  that  the 
coloring  of  autumn  leaves  is  due  to  frost.  In 
mild  seasons  the  trees  are  often  completely  turned 
before  the  thermometer  has  once  sunk  below  the 
freezing-point.  The  first  change  of  color  is  a  sure 
sign  that  the  tree  is  preparing  for  the  winter,  and 


TREES    IN   WINTER.  73 

that  a  change  in  the  cell-contents  of  the  leaves 
has  begun.1 

The  process  of  making  food  is  carried  on  in 
these  leaf-cells.  "  They  are  the  factories  where 
starch,  or  something  very  similar,  is  made." 2  The 
raw  material  brought  from  the  ground  is  here 
changed  into  food,  on  which  plants  and  animals 
can  live.  Throughout  the  summer  food  has  been 
constantly  made  and  carried  from  the  leaves  to 
other  parts  of  the  plant,  where  it  has  been  used 
for  food,  or  stored  as  a  reserve  for  the  future. 
When  this  activity  ceases,  and  the  leaves  fall  from 
the  tree,  it  would  be  a  great  waste  of  valuable 
material  if  all  the  food  contained  in  their  cells 
were  to  be  lost.  Nature  permits  no  such  waste. 
In  autumn,  when  the  life  of  the  leaf  is  nearly 
at  an  end,  its  food  materials  are  withdrawn  and 
deposited  in  the  stem  and  branches,  for  use  in  the 
following  spring.  This  withdrawal  is  preceded  by 
the  breaking  up  of  the  contents  of  the  cells.  The 
chlorophyll  —  the  green  coloring-matter  of  the 
leaves  —  is  decomposed  ;  and  the  products  of  this 
change,  together  with  the  starch  and  other  food 

1  Sachs,  "Die  Entleerung  der  Blatter  ira  Herbst."    Flora.     1863. 
p.  200. 

2  "  Concerning  a  Few  Common  Plants."    By  G.  L.  Goodale.    Bos- 
ton  :  D.  C.  Heath  &  Co.     1886.    p.  30. 


74 


TREES    IN    WINTER. 


materials,  are  taken  into  the  interior  of  the  tree. 
A  little  yellow  or  red  coloring-matter  is  left  behind, 
and  it  is  this  which  gives  the  leaves  their  bright 
hues.  When  they  finally  fall,  they  are  mere  dead 


FIG.  12.      FALL  OF  THE    LEAF.      HORSECHESTNUT.     ("  Pflanzenleben.") 

husks,  emptied  of  nourishment,  and  of  no  further 
use  to  the  plant. 

When  the  leaf  falls,  a  scar  is  left  behind.  In 
plants  with  compound  leaves,  like  the  Horsechest- 
nut  or  the  Ash,  there  is  a  similar  scar  at  the  base 
of  each  leaflet  (Fig.  12).  The  process  which  causes 


TREES    IN    WINTER.  75 

the  fall  is  a  curious  and  interesting  one,  and  it 
begins  very  early  in  the  life  of  the  leaf.  At  the 
base  of  each  leaf-stalk  a  layer  of  cells  is  formed 
which  gradually  cuts  across  the  whole  petiole,  and 
finally  completely  separates  the  leaf  from  its  stalk, 
so  that  a  gust  of  wind,  or  the  mere  weight  of  the 
leaf,  is  sufficient  to  cause  it  u>  fall.  The  walls  of 
the  cells  of  this  separating  layer  generally  become 
thickened  and  waterproof  before  the  leaf  falls,  so 
that  the  scar  is  already  healed. 

This  process,  then,  is  one  that  is  a  part  of  the 
life-history  of  the  leaf,  and  is  not  caused  by 
changes  in  temperature.  In  climates  where  the 
plants  are  active  during  the  entire  year,  the  leaves 
fall  gradually.  As  new  leaves  are  formed,  the 
old  are  dispensed  with,  and  there  is  never  a  time 
when  the  plants  are  leafless.  But  in  our  climate 
most  of  the  trees  and  shrubs  are  leafless  for  a 
large  portion  of  the  year.  This  is  a  provision 
which  enables  the  plants  to  live  through  a  long 
period  of  cold.  By  the  loss  of  their  leaves,  and 
the  withdrawal  into  safe  places  of  all  their  food 
materials,  the  plants  are  able  to  survive  uninjured. 
The  fall  of  the  leaves  is  hastened,  although  not 
caused,  by  the  cold.  We  do  not  understand  ex- 
actly why  the  leaves  all  fall  at  once ;  we  can  only 


76  TREES   IN    WINTER. 

say,  that  in  our  climate,  probably  those  plants 
have  survived  and  increased  which  were  so  con- 
stituted that  a  long  period  of  rest  succeeded  a 
season  of  active  work.1 

In  countries  where  a  wet  season  is  followed  by 
a  hot,  dry  season,  the  plants  lose  their  leaves  when 
the  heat  begins.  Thus  excessive  cold  and  exces- 
sive heat  produce  the  same  effect. 

Another  advantage  to  the  plants  in  losing  their 
leaves  is  the  lessened  resistance  which  the  tree 
presents  to  storms,  and  especially  to  snow.  The 
weight  of  the  winter  snows  would  break  the  trees 
if  the  leaves  were  obliged  to  carry  such  a  load. 
We  sometimes  see  trees  badly  injured  in  this  way 
by  a  premature  snowstorm. 

Now  that  the  trees  are  divested  of  their  sum- 
mer dress,  we  see  that  the  provision  for  the  next 
season's  garment  has  been  already  made.  There 
are  the  buds  thickly  studding  the  branches.  Look 
at  the  strong  Horsechestnut  buds,  with  their  resin- 
ous, waterproof  covering,  and  think  of  the  won- 
derful sleep  of  the  leaves  within,  wrapped  in  their 
woollen  blankets,  and  awaiting  only  the  warmth 
and  moisture  of  spring  to  burst  into  renewed  vigor 
(Fig.  13).  After  one  has  studied  naked  branches, 

1  "Pflanzenleben/'I.p.  329. 


TREES    IN    WINTER. 


77 


FIG.  13.     HORSECHESTNUT. 
Branch  in  Winter  State.     2.  An  Expanding  Leaf- Bud.      3.  Same,  more  advanced. 


78  TKEES    IN    WINTER. 

the  trees  become  as  beautiful  and  as  distinctive  in 
their  winter  clothing  as  when  they  are  leafy  and 
green. 

If  we  examine  a  branch  early  in  the  summer, 
we  shall  find  that  the  growth  of  the  next  season's 
buds  has  already  begun.  At  the  ends  of  the 
branches  and  in  the  leaf-axils  the  new  buds  are 
forming,  to  be  completed  and  covered  with  some 
protective  envelope  in  the  fall.  Through  the  bitter 
winter  they  remain  thus,  safely  covered  from  wet, 
and  protected  from  the  changes  of  the  season. 
Let  us  examine  some  of  the  protective  contriv- 
ances of  the  buds. 

Many  leaves  in  the  bud  are  invested  completely 
in  a  garment  of  wool  or  down,  which  is  a  non- 
conductor, and  saves  them  from  being  exposed  to 
sudden  changes.  Young  Horsechestnut  leaves  are 
thus  densely  clothed  with  wool,  and  the  young 
leaves  of  the  Beech  are  covered  with  silky  hairs 
(Fig.  19).  Sometimes  the  bud-scales  are  lined  with 
down,  as  are  the  inner  scales  of  the  Red  Maple. 

The  buds  are  usually  covered  by  scales,  which 
consist  of  leaves,  stipules,  or  flower-stalks,  modi- 
fied for  the  purpose  of  protection.  In  the  Lilac  the 
scales  pass  so  gradually  into  leaves,  that  it  is  hard 
to  draw  any  distinction  between  them  (Fig.  14). 


TREES    IN    WINTER.  79 

The  scales  of  the  Elm,  the  Beech,  the  Tulip-tree 
(Fig.  18),  and  Magnolia  are  stipules,  and  those  of 
the  Horsechestnut  are  modified  leaf-stalks.  In  all 


I.  Branch  in  Winter  State  (reduced).  2.  Same,  less  reduced.  3.  Branch,  with  Leaf-Buds 
expanded.  4.  Series  in  a  Single  Bud,  showing  the  Gradual  Transition  from  Scales  to 
Leaves. 

these  cases  the  outer  scales  have  become  thickened 
and  hardened,  so  as  the  better  to  protect  the  bud. 
Often  they  are  covered  with  resinous  or  waxy 


80  TKEES    IN    WINTER. 

matter  to  keep  out  the  wet  more  effectually,  as  in 
the  Horsechestnut.  The  Balm-of-Gilead  has  bud- 
scales  thickly  covered  with  a  yellow  substance, 
which  is  strongly  aromatic. 

Occasionally  we  find  a  plant  with  naked  buds, 
like  the  Hobble-bush  ( Viburnum  lantanoides).  This 
plant  contrives  to  live  without  any  covering  at  all 
for  its  buds. 

The  shape  of  a  tree  is  better  seen  in  winter 
than  at  any  other  time.  There  is  then  nothing 
to  hide  its  outline,  and  the  student  of  nature  will 
find  nothing  more  admirable  than  these  tree-forms. 
He  will  admire  them  none  the  less  because  he 
.connects  the  growth  of  the  buds  with  the  form  of 
the  tree,  and  understands  how  the  position,  the 
number,  the  non-development  of  some  buds,  and 
the  rapid  growth  of  others  have  affected  the  shape 
of  the  tree. 

He  sees  that  after  the  Elm  has  attained  a  certain 
height  the  terminal  buds  are  uniformly  undevel- 
oped, and  that  the  axillary  buds  are  exceedingly 
numerous.  This  makes  the  branches  dissolve  into 
many  shoots,  and  these  into  finer  spray,  and  helps 
to  give  the  tree  its  exquisite  grace  (Fig.  15) .  When 
he  looks  at  the  rough  bough  of  a  Horsechestnut, 
he  recognizes  that  the  flower-clusters  have  contin- 


TBEES    IN    WINTER. 


81 


FIG.  15.     ELM    TREE    IN    WINTER. 


82  TREES    IN    WINTER. 

ually_interrupted  the  growth  of  the  branch,  and 
that  another  bud  has  grown  from  a  leaf-axil  to 
supply  its  place ;  while  in  the  straight  branches  of 
the  Beech  the  terminal  bud  has  carried  on  each 
bough  year  after  year.  He  knows  that  the  rough- 
ness of  the  apple  and  cherry  twigs  (Fig.  16)  are 
due  to  the  multiplication  of  bud  and  leaf  scars, 
caused  by  the  very  small  yearly  growth ;  and  that 
the  Lilac-bush  is  continually  forked  because  the 
axillary  buds  have  grown  and  the  terminal  bud 
has  been  suppressed  (Fig.  14).  And  this  under- 
standing of  the  ways  of  growth  should  open  his 
eyes  the  more  to  the  variety  and  beauty  they 
create. 

When  the  winter  is  safely  passed,  the  first  per- 
ceptible change  that  takes  place  in  the  tree  is  the 
conversion  of  the  dry,  starchy  food  materials  stored 
in  the  branches  into  a  sugary  sap.1  This  chemical 
change  is  largely  brought  about  by  the  absorption 
of  water.  The  liquid  thus  produced  occupies  a 
greater  space  than  did  the  dry  starch,  and  causes 


1  "The  stimulus  to  the  movements  of  material,  however,  is  always 
given  by  the  growth  of  the  young  organs.  The  buds  of  a  tree  put 
forth  shoots  in  the  spring  by  no  means  because  the  nutritive  sap  enters 
into  them,  as  people  are  in  the  habit  of  saying,  but  exactly  the  reverse  : 
the  nutritive  matters  are  set  in  motion  because  the  buds  begin  to 
grow."  Sachs,  "  Lectures  on  the  Physiology  of  Plants,"  p.  364. 


TREES    IN    WINTER. 


83 


a  pressure  which  forces  the  sap  into  every  twig  of 
the  tree.  The  most  fa- 
miliar illustration  of  the 
flow  of  sap  in  the  spring 
is  the  Sugar-Maple.  The 
pressure  of  the  sap  forces 
a  stream  of  liquid  to  flow 
from  holes  bored  in  the 
bark  of  the  tree.  The  old 
idea  that  the  sap  descends 
into  the  root  of  a  tree  in 
the  fall,  and  rises  in  the 
spring,  is  erroneous. 

Then  follows  the  most 
striking    phenomenon     of 
the  whole  year.    The  mild 
days  come.    The  supply  of  food  in 
the  twigs  is  drawn  up  by  the  buds ; 
they  swell,  they  burst,  and  the  leaves 
begin   to   expand.     A   single  week 
has  wrought  a  miracle  whose  wonder 
never  grows  less.      It   has   always 
been  the  symbol  of  spiritual  renewal 
and  the  source  of  poetry,  and  it  will 
ever  be  so,  however  far  we  may  trace 
the  physical  causes  of  the  change. 


FIG.  16.      BRANCH 
OF   CHERRY. 


84  YOUNG    AND    OLD    LEAVES. 


VIII. 

YOUNG    AND    OLD    LEAVES.1 

OBSERVE  a  young  leaf  which  has  just  raised 
itself  above  the  ground,  or  one  still  half  hidden 
between  the  cotyledons  of  a  seedling,  or  lying 
within  the  opening  scales  of  a  bud.  The  very  part 
which  performs  the  functions  peculiar  to  the  leaf, 
breathing  out  water  and  producing  organized  sub- 
stances, is  far  behind  in  its  development ;  while 
the  ribs  stand  strongly  out,  the  green  tissue  is 
entirely  immature.  It  is  not  merely  that  the  ex- 
tent of  surface  is  small,  but  the  skin  of  the  leaf 
is  not  really  formed ;  the  outer  walls  of  the  epi- 
dermal cells  are  not  protected  by  cork,  are  neither 
water-tight  nor  impenetrable  by  water-vapor.  This 
unprotected  green  tissue  would  soon  become  dry 
if  spread  out  to  the  sunshine  and  the  wind.  The 
conditions  are  the  same  whether  the  young  leaf 
has  just  pushed  out  of  the  ground,  or  is  expanding 
from  a  bud,  or  pressing  out  from  between  the 

1  Translated  from  the  German  of  Dr.  A.  Kerner  von  Marilaun. 
"  Pflanzenleben."  Vol.  I.  p.  321. 


YOUNG    AND    OLD    LEAVES-  85 

cotyledons.  It  takes  some  time  for  the  parts 
which  hold  the  green  tissue  to  develop  fully,  and 
therefore  it  requires  very  effective  protective  con- 
trivances to  allow  the  young  leaves,  exposed  to 
the  changes  of  the  weather,  to  grow  normally  and 
form  unhurt  their  green,  transpiring  tissue.  These 
contrivances  are  sometimes  peculiar  to  young, 
undeveloped  leaves ;  sometimes  they  may  also  be 
observed  in  full-grown  leaves. 

The  diminution  of  the  extent  of  the  upper  sur- 
face, which  is  directly  exposed  to  the  air  and  the 
wind,  the  vertical  position  of  the  leaves,  and  the 
covering  of  the  green  tissue  under  a  protecting 
mantle  are  the  most  important  means  of  defence. 

The  small  amount  of  surface  exposed  to  the  air 
and  sun  is  necessitated  by  the  position  of  the  leaf 
in  the  bud.  In  the  bud  the  room  is  very  limited, 
and  the  leaves  are  packed  tightly  into  this  room, 
so  that  their  surfaces  are  rolled,  folded,  or  crumpled. 
This  is  also  an  advantage  when  they  emerge  to 
the  light  of  day  :  it  prevents  the  green  tissue  from 
becoming  dry,  is  continued  until  other  protective 
appliances  are  formed,  and  remains  in  some  cases 
throughout  the  life  of  the  plant. 

Many  leaves  are  rolled  in  the  bud,  especially 
in  bulbous  plants.  The  midrib,  or  often  quite  a 


86  YOUNG   AND    OLD    LEAVES. 

wide  strip  in  the  middle  of  the  leaf,  remains  flat, 
but  the  margins  are  rolled  up,  sometimes  on  the 
upper,  sometimes  on  the  under  side.  The  side  on 
which  the  stomata  are  most  numerous  and  the 
green,  transpiring  tissue  is  pierced  with  air-pas- 
sages, is  always  concave.  In  the  Crocus  the  two 
margins  are  rolled  outwards  and  united  by  a  broad, 
white,  flat  stripe,  and  in  the  Star-of-Bethlehem 
(Ornithogalum),  whose  leaves  are  marked  with  a 
similar  white  stripe,  the  halves  are  rolled  inwards. 
In  the  Crocus  the  stomata  are  on  the  under  side, 
in  the  Star-of-Bethlehem  on  the  upper  side  of  the 
leaf.  The  young  leaves  of  Ferns  are  also  rolled 
together,  but  the  midrib,  instead  of  being  flat,  is 
rolled  inward  spirally,  like  a  watch  spring,  so  that 
the  green  segments,  springing  from  either  side  of 
the  midrib,  are  packed  closely  one  upon  the  other. 
Less  common  than  leaves  which  are  rolled  are 
those  which  are  crumpled  in  the  bud.  Here  the 
netted  veins  make  a  firm  trellis  work,  or  grating, 
in  the  meshes  of  which  the  green  tissue  of  the 
leaf  appears  as  if  blistered,  and  the  whole  leaf 
has  the  effect  of  a  crumpled  cloth.  This  is  called 
corrugate  or  crumpled  vernation.  Especially  strik- 
ing in  this  respect  are  the  young  leaves  of  many 
species  of  Dock  (Rumex),  Rhubarb  (Rheum),  and 


YOUNG    AND    OLD    LEAVES.  87 

some  Primroses  (Primula).  A  leaf  is  often  both 
crumpled  and  rolled,  the  crumpled  leaves  having 
their  margins  rolled  up  in  the  bud. 

The  commonest  kind  of  vernation  is  folding. 
In  this  form  the  ribs  are  flat,  and  only  the  green 
tissue  between  the  ribs  lies  in  folds.  The  manner 
of  folding  varies  according  to  the  form  and  dis- 
tribution of  the  ribs  of  the  leaf.  When  the  leaf 
has  many  radial  ribs,  like  the  Lady's  Mantle 
(Alchemilla,  Fig.  177),  the  leaf  is  folded  in  the  bud 
like  a  fan.  The  ribs,  which  in  the  full-grown  leaf 
diverge  like  rays,  lie  side  by  side,  and  the  tissue, 
which  eventually  is  stretched  out  flat,  makes  deep 
folds,  pressed  one  upon  the  other.  If  each  of  the 
ribs  makes  the  midrib  of  a  segment,  as  in  Five- 
finger  (Potentilla)  and  Oxalis  (Fig.  178),  the  fold- 
ing is  the  same ;  each  leaflet  is  folded  along  the 
midrib  like  a  sheet  of  paper,  and  these  folded  leaf- 
lets lie  together  like  the  sheets  of  paper  in  a  box. 

When  the  leaves  are  feather-veined  and  the  leaf- 
lets are  opposite  each  other  on  a  common  stalk, 
like  the  leaves  of  Rose  and  Walnut  (Fig.  173' 4), 
they  are  folded  together  along  the  midrib  and  laid 
one  upon  the  other.  In  the  Rose  the  common  stalk 
is  so  short  in  the  bud  that  the  leaflets  all  seem  to 
come  from  the  same  point  like  the  Potentilla.  In 


88 


YOUNG    AND    OLD    LEAVES. 


most  Maple  leaves  the  folding  is  not  along  the 
ribs,  but  along  the  short  side  nerves.  Between 
these  large  folds  are  smaller  ones,  and  so  this  form 


FIG.  17.     VERNATION. 

I,  2,  of  the  Cherry  (Prunus  Avium);  3,  4,  of  the  Walnut  (Juglans  regia);  5,  6,  of  the  Snow- 
ball (Viburnum  Lantana);  7,  of  the  Lady's  Mantle  (Alchemilla  vulgaris);  8,  of  the 
Wood-Sorrel  (Oxalis  acetosella).  ("  Pflanzenleben.") 

of  vernation  makes  a  connecting  link  with  corru- 
gate vernation. 

The  folding  of  the  leaves  of  the  Beech,  the  Oak, 
and  many  other  plants  is  peculiar.     Every  leaf  has 


YOUNG    AND    OLD    LEAVES,  89 

a  midrib  with  the  veins  running  out  on  either  side, 
like  the  bones  on  the  vertebral  column  of  a  fish. 
The  green  tissue  makes  deep  folds  between  these 
veins,  which  lie  upon  each  other  like  the  folds  of 
a  fan  (Fig.  19).  The  folding  is  different  in  the 
Cherry  (Fig.  IT' 2).  Every  leaf  is  folded  along  the 
midrib  in  the  bud,  and  remains  so  for  some  time 
after  it  has  expanded.  The  two  halves  lie  so  close 
together  and  cover  each  other  so  perfectly,  that  at 
first  sight  they  appear  to  be  one.  Besides  this, 
they  are  firmly  united  by  a  balsam-like  substance. 
They  are  also  always  erect  in  this  stage  of  their 
development,  which  brings  us  to  another  contriv- 
ance which  can  be  observed  in  young,  undeveloped 
leaves. 

We  may  affirm  that  except  in  the  case  of  a 
few  corrugate  forms,  the  surfaces  of  young  leaves, 
whether  escaping  from  the  earth,  the  cotyledons,  or 
the  bud,  are  never  parallel  with  the  ground.  The 
green,  transpiring,  tender  parts,  especially,  have 
always  at  first  a  vertical  position,  and  their  sur- 
faces are  turned  sideways,  as  in  stems  which  serve 
the  purpose  of  leaves  (pliyllodadia  and  phyllodia 1), 

1  These  are  stems  or  petioles  which  serve  as  leaves.  Myrsiphyllum, 
known  in  our  greenhouses  as  Smilax,  is  an  example  of  a  branch  acting 
the  part  of  a  leaf,  and  in  Acacia  the  adult  foliage  is  formed  of  leaf- 
stalks. 


90  YOUNG   AND    OLD    LEAVES. 

the  equitant  leaves  of  Iris,  the  leaves  of  the  Com- 
pass Plant,1  and  the  folded  leaves  of  Grasses  in 
dry  weather.  Either  the  whole  outspread  or 
rolled  surface  of  the  leaf  is  erect,  as  in  most 
bulbous  plants,  or  the  midrib  of  the  leaf  may  be 
bent  towards  the  horizon.  In  the  latter  case,  the 
two  margins  make  a  single  edge,  turned  away 
from  the  rays  of  the  midday  sun,  as  in  some  Grasses 
(Glyceria,  Poo)  and  in  the  Cherry-tree.  Some- 
times the  petiole  is  upright,  and  the  tender  tissue 
is  drawn  down  over  it  like  a  shut  umbrella,  as  in 
Podophyllum,  and  several  of  the  Crowfoot  family. 
In  the  Horsechestnut  the  folded  segments  of  the 
leaves  issuing  from  the  bud  are  upright ;  then  they 
droop,  so  that  their  points  are  directed  to  the 
earth ;  and  later,  when  their  epidermis  is  more 
thickened,  they  raise  themselves  again  till  they 
are  nearly  parallel  with  the  ground.  Sometimes 
the  upward-growing  petiole  is  bent  over  in  the 
form  of  a  bow,  and  the  folded  leaves  hang  verti- 
cally on  the  curved  end,  as  in  the  common  Oxalis 
(Oxalis  acetosella)  and  many  other  plants  (Fig. 
178). 

1  The  blades  of  the  Compass  Plant  (Silphium  laciniatum)  take  a 
vertical  position,  by  the  leaves  making  a  half  twist.  On  the  prairies 
the  direction  of  the  leaves  is  usually  north  and  south. 


YOUNG    AND    OLD    LEAVES.  91 

Screens  and  coverings  of  various  kinds  are  an- 
other form  of  protection  for  the  tender  undeveloped 
parts  of  young  leaves.  This  covering  is  usually 
formed  of  stipules,  which  in  Beeches,  Lindens, 
Oaks,  Magnolias,  and  many  other  plants  are  mem- 
branaceous,  pale,  and  almost  destitute  of  chlo- 
rophyll. They  form  scales,  which  envelop  the 
young  leaves  pressing  from  the  bud,  which  they 
often  protect  from  the  rays  of  the  sun.  When 
the  leaf  has  outgrown  this  covering  and  needs  it 
no  longer,  the  scales  wither,  detach  themselves, 
and  fall  to  the  ground.  In  Oak  and  Beech  woods 
as  soon  as  the  leaves  have  reached  their  normal 
size,  millions  of  such  scales,  which  are  called  by 
botanists  "  deciduous  stipules,"  may  be  found. 
Very  deciduous  are  the  stipules  of  the  Tulip-tree 
(Fig.  18),  a  kind  of  Magnolia,  native  in  North 
America,  but  now  cultivated  in  every  part  of 
Europe.  The  stipules  are  large,  scaly,  and  placed 
together  in  pairs,  so  as  to  form  a  sort  of  sack.  In 
this  membranaceous,  somewhat  transparent  sack 
is  enclosed  the  young  leaf,  whose  stalk  is  bent  over 
upon  itself,  and  whose  blade  is  folded  along  the 
midrib,  like  the  leaf  of  Cherry.  The  leaf  grows 
there,  as  if  in  a  little  hothouse,  till  the  cells  of  its 
skin  are  so  thick  that  there  is  no  more  danger  of 


92 


YOUNG    AND    OLD    LEAVES. 


its  becoming  dried  up.     Then  the  sack  opens,  the 
two  scaly  stipules  fall  apart,  shrivel,  and  finally 


Fig.  18.     VERNATION    OF   THE   TULIP-TREE    (Liriodendron  Tulipifera). 
("  Pflanzenleben.") 

fall  off.  There  remain  only  two  scars  at  the  base 
of  the  leaf-stalk  to  remind  us  that  here  in  spring 
were  two  stipules,  which  protected  the  tender  young 
leaves  from  too  great  evaporation  of  water. 


YOUNG    AND    OLD    LEAVES.  93 

The  coats  of  resin  that  often  appear  on  young 
leaves  also  preserve  them  from  too  great  evapora- 
tion, and  when  the  leaf  is  fully  expanded  and  the 
skin  has  become  thickened,  they  finally  disappear. 
It  is  a  great  protection  for  the  leaves  just  escaped 
from  the  bud  to  be  clothed  with  hairs.  In  a  great 
many  plants  the  leaves  are  only  hairy  in  the  begin- 
ning of  their  development.  The  Silver  Poplar,  the 
Pear,  and  the  Mountain  Ash  are  examples  of  this. 
The  leaves  of  the  Horsechestnut  are  thickly  cov- 
ered with  wool  when  they  push  forth  from  the 
brown  scales  which  they  have  forced  apart,  but 
they  lose  this  wool  in  the  coarse  of  the  spring  so 
completely,  that  in  the  full-grown  leaves  its  former 
presence  could  only  be  guessed  by  a  few  shreds 
which  hang  here  and  there  upon  them.  In  the 
Beech  (Facjus  sylvatica,  Fig.  19)  the  garment  of 
the  young  leaves  is  formed  of  silky  hairs,  and 
their  position  and  action  are  so  peculiar  that  it  is 
worth  the  trouble  to  examine  the  leaf  more  closely. 
At  the  first  glance  the  young  Beech  leaf  appears 
to  be  entirely  clothed  with  silk  on  its  under  side, 
but  on  looking  more  closely,  the  silky  hairs  are 
to  be  found  only  on  the  margin  and  the  side  ribs, 
while  the  green  tissue  of  the  leaf  is  not  hairy, 
but  in  fact  perfectly  bare.  But  as  the  green  tissue 


94 


YOUNG    AND    OLD    LEAVES. 


of  the  leaf  lies  in  deep  folds,  the  ribs  are  brought 
very  near  together,  and  the  long,  silky  hairs  on 
one  rib  project  far  over  the  next,  so  that  the  fur- 
rows between  are  covered,  and  the  effect  of  a  leaf 
clothed  wholly  with  silk  is  produced.  There  can 


FIG.  19.     VERNATION    OF   THE    BEECH. 

I.  Bud  beginning  to  expand.  2.  Same,  more  advanced,  showing  the  Leaves  between  the 
Scales.  3.  Same,  still  more  developed.  4.  Back  of  a  Young  Beech  Leaf,  showing 
the  Plicate  Folding.  5.  A  Part  of  the  Same  Leaf,  showing  the  Silky  Hairs.  6.  Upper 
Surface  of  Unfolded  Leaf  ;  the  Stipules  withered  and  about  to  fall.  7.  Cross-Section 
of  Leaf,  perpendicular  to  the  Midrib.  8.  Vertical  Section,  parallel  to  the  Midrib. 
("  Pflanzenleben.") 

be  no  doubt  about  the  meaning  of  these  hairs ;  they 
protect  the  tissue  from  the  rays  of  the  sun  until 
the  epidermis  is  sufficiently  thickened.  After  this 
thickening  has  taken  place,  the  folds  straighten, 


YOUNG    AND    OLD    LEAVES.  95 

the  leaf  takes  a  horizontal  instead  of  a  vertical 
position,  the  lower  side  is  turned  away  from  the 
sun,  and  the  role  of  the  hairs  is  completed.  They 
are  now  superfluous  and  drop  off,  or  remain  withered 
and  meaningless. 


96  LEAF-ARRANGEMENT. 


IX. 

LEAF-ARRANGEMENT.1 

MR.  RUSKIN,  in  one  of  his  most  exquisite  pas- 
sages, has  told  us  that  "  Flowers  seem  intended 
for  the  solace  of  ordinary  humanity :  children 
love  them ;  tender,  contented,  ordinary  people 
love  them.  They  are  the  cottager's  treasure ; 
and,  in  the  crowded  town,  mark,  as  with  a  little 
broken  fragment  of  rainbow,  the  windows  of  the 
workers  in  whose  heart  rests  the  covenant  of 
peace."  I  should  be  ungrateful,  indeed,  did  I  not 
fully  feel  the  force  of  this  truth ;  but  it  will  be 
admitted  that  the  beauty  of  our  woods  and  fields 
is  due  at  least  as  much  to  foliage  as  to  flowers. 

In  the  words  of  the  same  author,  "  The  leaves 
of  the  herbage  at  our  feet  take  all  kinds  of 
strange  shapes,  as  if  to  invite  us  to  examine 
them,  —  star-shaped,  heart-shaped,  spear-shaped, 
arrow-shaped,  fretted,  fringed,  cleft,  furrowed, 
serrated,  sinuated,  in  whorls,  in  tufts,  in  spires, 

1  "Flowers,  Fruits,  and  Leaves."  By  Sir  John  Lubbock.  Macmillan 
&  Co.  London,  1886.  p.  97. 


LEAF-ARRANGEMENT.  97 

in  wreaths,  endlessly  expressive,  deceptive,  fan- 
tastic, never  the  same  from  footstock  to  blossom, 
they  seem  perpetually  to  tempt  our  watchfulness 
and  take  delight  in  outstripping  our  wonder." 

Now,  why  is  this  marvellous  variety,  this  inex- 
haustible treasury  of  beautiful  forms  ?  Does  it 
result  from  some  innate  tendency  of  each  species  ? 
Is  it  intentionally  designed  to  delight  the  eye  of 
man  ?  Or  has  the  form,  and  size,  and  texture 
some  reference  to  the  structure  and  organization, 
the  habits,  and  requirements,  of  the  whole  plant  ? 

I  do  not  propose  now  to  discuss  any  of  the 
more  unusual  and  abnormal  forms  of  leaves ;  .  .  . 
I  propose,  rather,  to  ask  you  to  consider  the  struc- 
ture, and  especially  the  forms,  of  the  common, 
every-day  leaves  of  our  woods  and  fields.  .  .  . 

In  the  first  place,  let  us  consider  the  size  of  the 
leaf.  On  what  does  it  depend?  In  herbs  we 
very  often  see  the  leaves  decrease  towards  the  end 
of  the  shoot;  while  in  trees  the  leaves,  though 
not  identical,  are  much  more  uniform  in  size. 

Again,  if  we  take  a  twig  of  Hornbeam,  we  shall 
find  that  the  six  terminal  leaves  have  together  an 
area  of  about  14  square  inches,  and  the  section  of 
the  twig  has  a  diameter  of  .06  of  an  inch.  In  the 
Beech  the  leaves  are  rather  larger,  six  of  them 


98  LEAF-ARRANGEMENT. 

having  an  area  of  perhaps  18  inches ;  and,  corre- 
sponding with  this  greater  leaf-surface,  we  find 
that  the  twig  is  somewhat  stouter,  say  .09  of  an 
inch.  Following  this  up  we  shall  find  that,  cceteris 
paribus,  the  size  of  the  leaf  has  a  relation  to  the 
thickness  of  the  stem.  This  is  clearly  shown  in 
the  following  table  :  — 

Diameter  of  Stem        Approximate  Area  of  Six 
in  Inches.  Upper  Leaves  in  Inches. 

Hornbeam 06  14 

Beech 09  18 

Elm   .         .         .         .         .         .       .11  34 

Nut 13  55 

Sycamore 13  60 

Lime 14  60 

Chestnut 15  72 

Mountain  Ash 16  60 

Elder 18  93 

Ash 18  100 

Walnut 25  220 

Ailanthus  .....       .30  240 

Horsechestnut   ....       .30  300 

In  the  Elm  the  numbers  are  .11  and  34,  in  the 
Chestnut  .15  and  72,  and  in  the  Horsechestnut 
the  stem  has  a  thickness  of  .3,  and  the  six  leaves 
have  an  area  often  of  300  square  inches.  Of 
course,  however,  these  numbers  are  only  approxi- 
mate. Many  things  have  to  be  taken  into  con- 


LEAF-ARRANGEMENT.  99 

sideration.  Strength,  for  instance,  is  an  important 
element.  Thus  the  Ailanthus,  with  a  stem  equal 
in  thickness  to  that  of  the  Horsechestnut,  carries 
a  smaller  area  of  leaves ;  perhaps  because  it  is  less 
compact.  Again,  the  weight  of  the  leaves  must 
doubtless  be  taken  into  consideration.  Thus,  in 
some  sprays  of  Ash  and  Elder  of  equal  diameter, 
which  I  examined,  the  former  bore  the  larger  ex- 
panse of  leaves.  Not  only,  however,  is  the  stem 
of  the  Elder  less  compact,  but  the  Elder  leaves, 
though  not  so  large,  were  quite  as  heavy,  if  not, 
indeed,  a  little  heavier.  I  was  for  some  time  puz- 
zled by  the  fact  that,  while  the  terminal  shoot  of 
the  Spruce  is  somewhat  thicker  than  that  of  the 
Scotch  Fir,  the  leaves  are  not  much  more  than  a 
third  as  long.  May  this  not,  perhaps,  be  due  to 
the  fact  that  they  remain  on  the  tree  more  than 
twice  as  long,  so  that  the  total  leaf -area  borne  by 
the  branch  is  greater,  though  the  individual  leaves 
are  shorter  ?  Again,  it  will  be  observed  that  the 
leaf-area  of  the  Mountain  Ash  is  small  compared 
to  the  stem ;  and  it  may,  perhaps,  not  be  unrea- 
sonable to  suggest  that  this  may  be  connected 
with  the  habit  of  the  tree  to  grow  in  bleak  and 
exposed  situations.  The  position  of  the  leaves, 
the  direction  of  the  bough,  and  many  other  ele- 


106  LEAF-ARRANGEMENT. 

merits,  would  have  also  to  be  taken  into  consideraj 
tion ;  but  still  it  seems  clear  that  there  is  a  corre- 
spondence between  thickness  of  stem  and  size  of 
leaf.  This  ratio,  moreover,  when  taken  in  rela- 
tion with  the  other  conditions  of  the  problem,  has, 
as  we  shall  see,  a  considerable  bearing  not  only  on 
the  size,  but  also  on  the  form,  of  the  leaf.  .  .  . 

Perhaps  it  will  be  said  that  in  some  trees  the 
leaves  are  much  more  uniform  in  size  than  in 
others.  This  is  true.  The  Sycamore,  for  instance, 
varies  greatly.  In  the  specimen  tabulated  its  stem 
was  .13  in  diameter,  and  the  area  of  the  six  upper 
leaves  was  60  square  inches.  In  another  the  six 
upper  leaves  had  an  area  of  rather  over  a  hundred 
inches,  and  in  this  case  the  diameter  of  the  stem 
was  .18. 

Another  point  is  the  length  of  the  internode. 
In  such  trees  as  the  Beech,  Elm,  Hornbeam,  etc., 
the  distance  from  bud  to  bud  varies  comparatively 
little,  and  bears  a  tolerably  close  relation  to  the 
size  of  the  leaf.  In  the  Sycamore,  Maple,  etc.,  on 
the  contrary,  the  length  varies  greatly. 

Now,  if,  instead  of  looking  merely  at  a  single 
leaf,  we  consider  the  whole  bough  of  any  tree,  we 
shall,  I  think,  see  the  reason  of  their  differences 
of  form. 


LEAF-AHiUKGEMENT 


Let  us  begin,  for  instance,  with  the  common 
Lime  (Fig.  20).  The  leaf-stalks  are  arranged  at 
an  angle  of  about  40°  with  the  branch,  and  the 
upper  surfaces  of  the  leaves  are  in  the  same  plane 
with  it.  The  result  is,  they  are  admirably  adapted 
to  secure  the  maximum  of  light  and  air.  Let  us 


FIG.  20.     LIME. 


take,  for  instance,  the  second  or  third  leaf  in  Fig. 
20.  They  are  4?  inches  long  and  very  nearly  as 
broad.  The  distance  between  the  two  leaves  on 
(each  side  is  also  just  4i  inches,  so  that  they  ex- 
;actly  fill  up  the  interval.  In  Tilia  parvifolia  the 
.arrangement  is  similar,  but  leaves  and  internodes 
are  both  less;  the  leaves,  say,  1£  inch,  and  the 
internodes  .6. 


1 02  LEAF-ARRANGEMENT. 

In  the  Beech  the  general  plane  of  the  leaves  is 
again  that  of  the  branch  (Fig.  21),  but  the  leaves 
themselves  are  ovate  in  form,  and  smaller,  being 
only  from  2  to  3  inches  in  length.  On  the  other 
hand,  the  distance  between  the  internodes  is  also 
smaller,  being,  say,  li  inch  against  something  less 
than  2  inches.  The  diminution  in  length  of  the 


FIG.  21.     BEECH. 


internode  is  not,  indeed,  exactly  in  proportion  to 
that  of  the  leaf ;  but,  on  the  other  hand,  the  leaf 
does  not  make  so  wide  an  angle  with  the  stem. 
To  this  position  is  probably  due  the  difference  of 
form.  The  outline  of  the  basal  half  of  the  leaf 
fits  neatly  to  the  branch ;  that  of  the  upper  half 
follows  the  edge  of  the  leaf  beyond,  and  the  form 
of  the  inner  edge  being  thus  determined,  decides 
the  outer  one  also. 


LEAF-ARRANGEMENT.  103 

In  the  Nut  (Corylus)  the  internodes  are  longer, 
and  the  leaves  correspondingly  broader.  In  the 
Elm  the  ordinary  branches  have  leaves  resembling, 
though  rather  larger  than,  those  of  the  Beech; 
but  in  vigorous  shoots  (Fig.  22)  the  internodes 


FIG.  22.     ELM. 


become  longer,  and  the  leaves  correspondingly 
broader  and  larger,  so  that  they  come  nearly  to 
resemble  those  of  the  Nut. 

But  it  may  be  said  that  the  Spanish  Chestnut 
(Castanea  vulgaris,  Fig.  23)  also  has  alternate 
leaves,  in  a  plane  parallel  to  that  of  the  branch, 


104 


LEAF-ARRANGEMENT. 


and  with  internodes  of  very  nearly  the  same 
length  as  the  Beech.  That  is  true ;  but,  on  the 
other  hand,  the  terminal  branches  of  the  Spanish 
Chestnut  are  stouter  in  proportion.  Thus,  imme- 
diately below  the  sixth  leaf,  the  Chestnut  stalk 
may  be  .15  of  an  inch  in  thickness,  that  of  the 


FIG.  23.  CASTANEA. 


FIG.  24.  CASTANEA  AND  BEECH. 


Beech  not  much  more  than  half  as  much.  Con- 
sequently the  Chestnut  could,  of  course  supposing 
the  strength  of  the  wood  to  be  equal,  bear  a 
greater  weight  of  leaf  ;  but,  the  width  of  the  leaf 
being  determined  by  the  distance  between  the  in- 
ternodes, the  leaf  is,  so  to  say,  compelled  to  draw 
itself  out.  In  Fig.  24  I  have  endeavored  to  illus- 
trate this  by  placing  a  spray  of  Beech  over  one  of 


LEAF-ARRANGEMENT.  105 

Spanish  Chestnut.  Moreover,  not  only  do  the 
leaves  on  a  single  twig  thus  admirably  fit  in  with 
one  another,  but  they  are  also  adapted  to  the  rami- 
fications of  the  twigs  themselves.  .  .  . 

The  leaves  of  the  Yew  (Fig.  25)  belong  to  a 
type    very   different   from    those  which  we   have 


FIG.  25.     YEW. 


hitherto  been  considering.  They  are  long,  narrow, 
and  arranged  all  around  the  stem,  but  spread  right 
and  left,  so  that  they  lie  on  one  plane,  parallel  to 
the  direction  of  the  branchlet,  and  their  width 
bears  just  such  a  relation  to  their  distance  apart- 
that  when  so  spread  out  their  edges  almost  touch. 


106 


LEAF-ARRANGEMENT. 


The  leaves  of  Conifers  are  generally  narrow  and 
needle-like.  I  would  venture  to  suggest  that  this 
may  be  connected  with  the  absence  of  the  fibro- 
vascular  bundles,  which  are  present  in  the  stems 
of  dicotyledons,  such  as  the  Beech,  Oak,  etc.  The 
leaves  of  the  Scotch  Pine  are  needle-like,  1?  inches 
in  length,  and  TO  in  diameter.  They  are  arranged 


FIG.  26.     BOX. 


in  pairs,  each  pair  enclosed  at  the  base  in  a  sheath. 
One  inch  of  stem  bears  about  fifteen  pairs  of 
leaves.  Given  this  number  of  leaves  in  such  a 
space,  they  must  evidently  be  long  and  narrow. 
If  I  am  asked  why  they  are  longer  than  those  of 
the  Yew,  I  would  suggest  that  the  stem,  being 
thicker,  is  able  to  support  more  weight.  In  con- 
firmation of  this  we  may  take  for  comparison  the 


LEAF-ARRANGEMENT.  107 

Weymouth   Pine,  in  which  the   leaves  are  much 
longer  and  the  stalk  thicker. 

Fig.  26  represents  a  sprig  of  Box.  It  will  be 
observed  that  the  increase  of  width  in  the  leaves 
corresponds  closely  with  the  greater  distance  be- 
tween the  points  of  attachment. 


FIG.  27.     HCRSECHESTNUT. 

When  we  pass  from  the  species  hitherto  consid- 
ered to  the  Maples  (Fig.  29),  Sycamores,  and  Horse- 
chestnuts  (Figs.  27  and  28),  we  come  to  a  totally 
different  type  of  arrangement.  The  leaves  are 
placed  at  right  angles  to  the  axis  of  the  branch, 
instead  of  being  parallel  to  it,  have  long  petioles, 
and  palmate  instead  of  pinnate  veins.  In  this 
group  the  mode  of  growth  is  somewhat  stiff ;  the 
main  shoots  are  perpendicular,  and  the  lateral  ones 


108  LEAF-ARRANGEMENT. 

nearly  at  right  angles  to  them.  The  buds,  also, 
are  comparatively  few,  and  the  internodes,  conse- 
quently, at  greater  distances  apart,  sometimes  as 
much  as  a  foot,  though  the  two  or  three  at  the 
end  of  a  branch  are  often  quite  short.  The  gen- 


FIG.  28.     HORSECHESTNUT. 


eral  habit  is  shown  in  Figs.  27  and  28.  Now,  if 
we  were  to  imagine  six  Beech  or  Elm  leaves  on 
these  three  internodes,  it  is  obvious  that  the  leaf- 
surface  would  be  far  smaller  than  it  is  at  present. 
Again,  if  we  compare  the  thickness  of  an  average 
Sycamore  stem,  below  the  sixth  leaf,  with  that  of 


LEAF-ARRANGEMENT.  109 

a  Beech  stem,  it  is  obvious  that  there  would  be  a 
considerable  waste  of  power.  Once  more,  if  the 
leaves  were  parallel  to  the  branch,  they  would,  as 
the  branches  are  arranged,  be  less  well  disposed 
with  reference  to  light  and  air.  A  glance  at  Figs. 
27,  28,  29,  however,  will  show  how  beautifully  the 
leaves  are  adapted  to  their  changed  conditions. 
The  blades  of  the  leaves  of  the  upper  pair  form 
an  angle  with  the  leaf-stalks,  so  as  to  assume  a 
horizontal  position,  or  nearly  so ;  the  leaf-stalks  of 
the  second  pair  decussate  with  those  of  the  first, 
and  are  just  so  much  longer  as  to  bring  up  that 
pair  nearly  or  quite  to  a  level  with  the  first ;  the 
third  pair  decussate  with  the  second,  and  are  again 
brought  up  nearly  to  the-  same  level,  and  immedi- 
ately to  the  outside  of  the  first  pair.  In  well-grown 
shoots  there  is  often  a  fourth  pair  on  the  outside  of 
the  second.  If  we  look  at  such  a  cluster  of  leaves 
directly  from  in  front,  we  shall  see  that  they  gen- 
erally appear  somewhat  to  overlap ;  but  it  must  be 
remembered  that  in  temperate  regions  the  sun  is 
never  vertical.  Moreover,  while  alternate  leaves 
are  more  convenient  in  such  an  arrangement  as 
that  of  the  Beech,  where  there  would  be  no  room 
for  a  second  leaf,  it  is  more  suitable  in  such  cases 
as  the  Sycamores  and  Maples  that  the  leaves  should 


110  LEAF-ARRANGEMENT. 

be  opposite,  because  if,  other  things  remaining  the 
same,  the  leaves  of  the  Sycamore  were  alternate, 
the  sixth  leaf  would  require  an  inconvenient  length 
of  petiole. 

Perhaps  it  will  be  said  that  the  Plane-tree,  which 
has  leaves  so  much  like  a  Maple  that  one  species 
of  the  latter  genus  is  named  after  it  (Acer  plata- 


FIG.  29.     ACER. 


noides,  Fig.  29),  has,  nevertheless,  alternate  leaves. 
In  reality,  however,  I  think  this  rather  supports 
my  argument,  because  the  leaves  of  the  Plane, 
instead  of  being  at  right  angles  to  the  stem,  lie 
more  nearly  parallel  with  it.  Moreover,  as  any  one 
can  see,  the  leaves  are  not  arranged  so  successfully 
with  reference  to  exposure  as  those  of  the  species 
we  have  hitherto  been  considering,  perhaps  be- 
cause, living  as  it  does  in  more  southern  localities, 


LEAF-ARRANGEMENT.  Ill 

the  economy  of  sunshine  is  less  important  than 
in  more  northern  regions. 

The  shoot  of  the  Horsechestnut  is  even  stouter 
than  that  of  the  Sycamore,  and  has  a  diameter 
below  the  sixth  leaf  of  no  less  than  T36-  of  an  inch. 
With  this  increase  of  strength  is,  I  think,  con- 
nected the  greater  size  of  the  leaves,  which  attain 
to  as  much  as  18  inches  in  diameter;  and  this 
greater  size,  again,  has  perhaps  led  to  the  dis- 
section of  the  leaves  into  five  or  seven  distinct 
segments,  each  of  which  has  a  form  somewhat 
peculiar  in  itself,  but  which  fits  in  admirably  with 
the  other  leaflets.  However  this  may  be,  we  have 
in  the  Horsechestnut,  as  in  the  Sycamore  and 
Maples,  a  beautiful  dome  of  leaves,  each  standing 
free  from  the  rest,  and  expanding  to  the  fresh  air 
and  sunlight  a  surface  of  foliage  in  proportion  to 
the  stout,  bold  stem  on  which  they  are  borne. 

Now,  if  we  place  the  leaves  of  one  tree  on  the 
branches  of  another,  we  shall  at  once  see  how 
unsuitable  they  would  be.  I  do  not  speak  of  put- 
ting a  small  leaf,  such  as  that  of  a  Beech,  on  a 
large-leaved  tree,  such  as  the  Horsechestnut ;  but 
if  we  place,  for  instance,  Beech  on  Lime,  or  vice 
versa,  the  contrast  is  sufficiently  striking.  The 
Lime  leaves  would  overlap  one  another ;  while,  on 


112 


LEAF-ARRANGEMENT. 


the  other  hand,  the  Beech  leaves  would  leave  con- 
siderable interspaces.  Or  let  us  in  the  same  way 
transpose  those  of  the  Spanish  Chestnut  ( Castaned) 
and  those  of  Acer  platanoides,  a  species  of  Maple. 
I  have  taken  specimens  in  which  the  six  terminal 


FIG.  30.     LEAVES   OF   CASTANEA. 


leaves  of  a  shoot  of  the  two  species  occupy  approxi- 
mately the  same  area.  Figs.  23  and  29  show  the 
leaves  in  their  natural  position,  those  of  the  Span- 
ish Chestnut  lying  along  the  stalk,  while  those  of 
the  Maple  are  ranged  around  it.  In  both  cases 
it  will  be  seen  that  there  is  practically  no  over- 
lapping and  very  little  waste  of  space.  In  the 
Spanish  Chestnut  the  stalks  are  just  long  enough 


LEAF-ARRANGEMENT.  113 

to  give  a  certain  play  to  the  leaves.  In  Maple 
they  are  much  longer,  bringing  the  leaves  approxi- 
mately to  the  same  level,  and  carrying  the  lower 
and  outer  ones  free  from  the  upper  and  younger 
ones. 

Now,  if  we  arrange  the  Spanish  Chestnut  leaves 
round  a  centre,  as  in  Fig.  30,  it  is  at  once  obvious 


FIG.  31.     MAPLE    LEAVES   ON    CHESTNUT. 

how  much  space  is  wasted.  On  the  other  hand, 
if  we  place  the  leaves  of  the  Maple  on  the  stalk 
of  a  Spanish  Chestnut  at  the  points  from  which 
the  leaves  of  Chestnut  came  off,  as  in  Fig.  31,  we 
shall  see  that  the  stalks  are  useless,  and  even  mis- 
chievous as  a  cause  of  weakness  and  of  waste  of 
space ;  while,  on  the  other  hand,  if  we  omit  the 
stalks,  or  shorten  them  to  the  same  length  as  those 


114  LEAF-ARRANGEMENT. 

of  the  Chestnut,  as  in  Fig.  32,  the  leaves  would 
greatly  overlap  one  another. 

Once  more :  for  leaves  arranged  as  in  the  Beech 
the  gentle  swell  at  the  base  is  admirably  suited ; 
but  in  a  crown  of  leaves,  such  as  those  of  the 
Sycamore,  space  would  be  wasted,  and  it  is  better 
that  they  should  expand  at  once,  as  soon  as  their 


FIG.  32.     MAPLE    LEAVES   ON    CHESTNUT. 

stalks  have  borne  them  free  from  those  within. 
Moreover,  the  spreading  lobes  leave  a  triangular 
space  (Fig.  29)  with  the  insertion  of  the  stalk  at 
the  apex,  which  seems  as  if  expressly  designed  to 
leave  room  for  the  pointed  end  of  the  leaf  within. 
Hence  we  see  how  beautifully  the  whole  form 
of  these  leaves  is  adapted  to  the  mode  of  growth 
of  the  trees  themselves  and  the  arrangement  of 
their  buds. 


CLIMBING    PLANTS.  115 


X. 

CLIMBING    PLANTS. 

CHARLES  DUDLEY  WARNER,  in  "  My  Summer  in 
a  Garden/'  gives  the  following  description  of  the 
growth  of  a  vine :  "  I,  however,  believe  in  the  in- 
tellectual, if  not  the  moral,  qualities  of  vegetables, 
and  especially  weeds.  There  was  a  worthless  vine 
that  (or  who)  started  up  about  midway  between  a 
grape-trellis  and  a  row  of  bean-poles,  some  three 
feet  from  each,  but  a  little  nearer  the  trellis. 
When  it  came  out  of  the  ground,  it  looked  around 
to  see  what  it  should  do.  The  trellis  was  already 
occupied ;  the  bean-pole  was  empty.  There  was 
evidently  a  little  the  best  chance  of  light,  air, 
and  sole  proprietorship  on  the  pole ;  and  the  vine 
started  for  the  pole,  and  began  to  climb  it  with  de- 
termination. Here  was  as  distinct  an  act  of  choice, 
of  reason,  as  a  boy  exercises  when  he  goes  into  a 
forest,  and,  looking  about,  decides  which  tree  he 
will  climb.  And,  besides,  how  did  the  vine  know 
enough  to  travel  in  exactly  the  right  direction,  three 
feet,  to  find  what  it  wanted  ?  This  is  intellect." 


116  CLIMBING   PLANTS. 

This  expresses  very  prettily  a  thing  which  every 
garden-lover  must  have  noticed,  —  that  a  vine  will 
find  out  its  support  anywhere  within  a  reasonable 
distance.  Of  course,  the  choice  between  the  trellis 
and  the  pole  is  a  genial  fancy  of  the  gardener ; 
but  it  is  a  fact  that  a  plant  with  tendrils  will 
find  out  and  clasp  a  stick  placed  at  a  short  dis- 
tance from  it  on  any  side,  and,  similarly,  that 
a  Morning-Glory  will  wind  about  a  pole  in  its 
neighborhood,  on  whichever  side  this  may  happen 
to  be.  The  explanation  of  this  curious  phenome- 
non was  sought  and  found  by  Charles  Darwin, 
and  he  was  led  to  study  the  subject  in  the  follow- 
ing way. 

In  August,  1858,  Dr.  Gray  read  a  short  "  Note 
on  the  Coiling  of  Tendrils  "  before  the  American 
Academy  of  Arts  and  Sciences.1  In  this  paper  he 
spoke  of  the  views  of  a  German,  Hugo  von  Mohl, 
who  had  published  a  book  on  the  subject  twenty 
years  before.2  Von  Mohl  said  that  the  coiling  was 
due  to  an  irritability  excited  by  contact,  that  it 
was  of  the  same  nature  as  the  closing  of  the  leaves 
of  the  Sensitive  Plant  at  the  touch.  Dr.  Gray 


1  "Proe.  Amer.  Acad.  of  Arts  and  Sciences."     1858. 

2  "Ueber  das  Bau  und  das  Winden  der  Ranken  und  Schlingpflan- 
zen."     1827. 


CLIMBING    PLANTS.  117 

indorsed  this  view,  and  gave  his  own  observations 
thus : — 

"The  tendrils  in  several  common  plants  will 
coil  up  more  or  less  promptly  after  being  touched, 
or  brought  with  a  slight  force  into  contact  with  a 
foreign  body,  and  in  some  plants  the  movement  of 
coiling  is  rapid  enough  to  be  directly  seen  by  the 
eye ;  indeed,  is  considerably  quicker  than  is  needful 
for  being  visible.  And,  to  complete  the  parallel, 
as  the  leaves  of  the  Sensitive  Plant  and  the  like, 
after  closing  by  irritation,  resume  after  a  while 
their  ordinary  expanded  positions,  so  the  tendrils  in 
two  species  of  the  Cucurbit acece,  or  Squash  family, 
experimented  upon,1  after  coiling  in  consequence 
of  a  touch,  will  uncoil  into  a  straight  position  in 
the  course  of  an  hour ;  then  they  will  coil  up  at  a 
second  touch,  often  more  quickly  than  before  ;  and 
this  may  be  repeated  three  or  four  times  in  the 
course  of  six  or  seven  hours. 

"  My  cursory  illustrations  have  been  principally 
made  upon  the  Bur-Cucumber  (Sicyos  angulatus). 
To  see  the  movement  well,  full-grown  and  out- 
stretched tendrils,  which  have  not  reached  any 
support,  should  be  selected,  and  a  warm  day ; 
77  F.  is  high  enough. 

1  "  Sicyos  angulatus  und  Echinocystis  lobata." 


118  CLIMBING    PLANTS. 

"  A  tendril  which  was  straight,  except  a  slight 
hook  on  the  tip,  on  being  gently  touched  once  or 
twice  with  a  piece  of  wood  on  the  upper  side, 
coiled  at  the  end  into  2  £-3  turns  within  a  minute 
and  a  half.  The  motion  began  after  an  interval 
of  several  seconds,  and  fully  half  of  the  coiling 
was  quick  enough  to  be  very  distinctly  seen.  After 
a  little  more  than  an  hour  had  elapsed,  it  was 
found  to  be  straight  again.  The  contact  was  re- 
peated, timing  the  result  by  the  second-hand  of  a 
watch.  The  coiling  began  within  four  seconds, 
and  made  one  circle  and  a  quarter  in  about  four 
seconds. 

"  It  had  straightened  itself  again  in  an  hour 
and  five  minutes  (perhaps  sooner,  but  it  was  then 
observed) ;  and  it  coiled  the  third  time  on  being 
touched  rather  firmly,  but  not  so  quickly  as  before ; 
viz.,  li  turns  in  half  a  minute. 

"I  have  indications  of  the  same  movement  in 
the  tendrils  of  the  Grape-vine ;  but  a  favorable 
day  has  not  occurred  for  the  experiment  since  my 
attention  was  first  directed  to  the  subject." 

This  paper  set  Darwin  also  to  studying  climbers. 
In  1863  he  writes  to  Sir  Joseph  Hooker :  * — 

1  "Life  and  Letters  of  Charles  Darwin/'  By  Francis  Darwin. 
Vol.  II.  p.  484. 


CLIMBING    PLANTS.  119 

MY  DEAR  HOOKER, — I  have  been  observing  pretty  care- 
fully a  little  fact  which  has  surprised  me ;  and  I  want  to 
know  from  you  and  Oliver  whether  it  seems  new  or  odd 
to  you ;  so  just  tell  me  whenever  you  write :  it  is  a  very 
trifling  fact,  so  do  not  answer  on  purpose. 

I  have  got  a  plant  of  Echlnocystis  lobata  [Fig.  33]  to 
observe  the  irritability  of  the  tendrils  described  by  Asa 
Gray,  and  which,  of  course,  is  plain  enough.  Having  the 
plant  in  my  study,  I  have  been  surprised  to  find  that  the 
uppermost  part  of  each  branch  (i.e.,  the  stem  between 
the  two  uppermost  leaves  excluding  the  growing  tip)  is  con- 
stantly and  slowly  twisting  round,  making  a  circle  in  from 
one-half  to  two  hours.  It  will  sometimes  go  round  two  or 
three  times,  and  then  at  the  same  rate  untwists  and  twists 
in  opposite  directions.  It  generally  rests  half  an  hour 
before  it  retrogrades.1  The  stem  does  not  become  perma- 
nently twisted.  The  stem  beneath  the  twisting  portion 
does  not  move  in  the  least,  though  not  tied.  The  move- 
ment goes  on  all  day  and  all  early  night.  It  has  no  relation 
to  light,  for  the  plant  stands  in  my  window,  and  twists 
from  the  light  just  as  quickly  as  towards  it.  This  may  be 
a  common  phenomenon  for  what  I  know,  but  it  confounded 
me  quite  when  I  began  to  observe  the  irritability  of  the 
tendrils.  I  do  not  say  it  is  the  final  cause,  but  the  result  is 
pretty ;  for  the  plant,  every  one  and  a  half  or  two  hours, 

1  This  reversal  of  the  direction  of  the  movement  is  not  the  normal 
method  of  the  plant.  lie  s  js  of  it  afterward  ("Climbing  Plants," 
p.  128),  "  The  course  generally  pursued  was  with  the  sun,  but  often  in 
an  opposite  direction.  Sometimes  the  movement  during  a  short  time 
would  either  stop  or  be  reversed ;  and  this  apparently  was  due  to  inter- 
ference from  the  light,  as,  for  instance,  when  I  placed  a  plant  close  to 
a  window." 


120  CLIMBING    PLANTS. 

sweeps  a  circle  (according  to  the  length  of  the  bending 
shoot  and  the  length  of  the  tendril)  of  from  one  foot  to 
twenty  inches  in  diameter,  and  immediately  that  the  tendril 
touches  any  object,  its  sensitiveness  causes  it  immediately 
to  seize  it.  A  clever  gardener,  my  neighbor,  who  saw  the 
plant  on  my  table  last  night,  said :  "  I  believe,  sir,  the  ten- 
drils can  see ;  for  wherever  I  put  a  plant  it  finds  out  any 
stick  near  enough."  I  believe  the  above  is  the  explanation, 
viz.,  that  it  sweeps  slowly  round  and  round.  The  tendrils 
have  some  sense,  for  they  do  not  grasp  each  other  when 

young. 

Yours  affectionately, 

C.  DARWIX. 


Here  he  has  found  the  explanation  of  the 
curious  fact  which  we  noticed  in  the  beginning  of 
this  article.  Two  years  later  his  paper  on  "  Climb- 
ing Plants "  was  printed  in  the  Journal  of  the 
Linnsean  Society,  and  in  1875  the  essay  was  re- 
vised and  published  as  a  separate  book. 

Darwin  divides  climbing  plants  into  four  classes : 
(1)  Twiners,  or  plants  which  climb  by  the  stem 
winding  about  its  support.  (2)  Leaf-climbers  and 
tendril-bearers,  plants  which  possess  irritable 
organs  by  which  they  grasp  any  object  with  which 
they  come  in  contact.  (3)  Hook-climbers.  (4) 
Root-climbers,  which  attach  themselves  by  means 
of  aerial  rootlets.  The  last  two  classes  have  no 


CLIMBING    PLANTS. 


121 


122  CLIMBING    PLANTS. 

special  movements,  and  we  shall  not  here  consider 
them. 

The  first  division  is  well  represented  by  the  Hop 
or  Morning-Glory.  If  we  observe  a  young  shoot 
which  has  grown  beyond  its  support  (Fig.  34, 
Morning-Glory),  we  can  see  that  its  tip  describes  a 
circle,  or  rather  an  ellipse.  This  is  not  caused  by 
the  twisting  of  the  shoot,  for  it  would  soon  break 
if  it  continued  to  twist  round  and  round.  We  can 
see,  by  holding  a  string  in  one  hand  and  twisting 
it  with  the  other,  how  great  a  strain  is  thus 
brought  to  bear.  Such  a  strain  would  at  once 
snap  a  delicate  stem  in  two. 

The  movement  is  caused  by  the  bowing  of  the 
shoot  successively  to  every  point  of  the  compass. 
If  we  hold  a  stick  upright,  we  can  bend  it  towards 
the  north,  then,  without  twisting  the  stick,  to  the 
northeast,  then  to  the  east,  and  so  on,  till  we  bend 
it  to  the  north  again.  If  we  make  a  mark  on  the 
upper  side  of  the  stick  when  it  is  bent  towards  the 
north,  the  mark  will  be  on  the  under  side  when 
the  stick  bows  towards  the  south.  Dr.  Gray  thus 
explains  this  bowing  movement : 1  "To  learn  how 
the  sweeps  are  made,  one  has  only  to  mark  a  line 

1  "How  Plants  Behave."  By  Asa  Gray.  Ivison,  Blakeman,  Taylor, 
&  Co.  1872.  p.  13. 


CLIMBING    PLANTS. 


123 


of  dots  along  the  upper  side  of  the  outstretched 
revolving  end  of  such  a  stem  (Fig.  34),  and  to  note 
that  when  it  has  moved  round  a  quarter  of  a  circle 
these  dots  will  be  on  one  side,  when  half  round 


the  dots  occupy  the  lower  side, 
and  when  the  revolution  is  com- 
pleted they  are  again  on  the 
upper  side.  That  is,  the  stem 
revolves  by  bowing  itself  over  to 
one  side;  is  either  pulled  over, 
or  pushed  over,  or  both,  by  some 
internal  force,  which  acts  in  turn 
all  round  the  stem  in  the  direc- 
tion in  which  it  sweeps ;  and  so 
the  stem  makes  -its  circuits  with- 
out twisting."  :  "  The  first  pur- 
pose of  the  spontaneous  revolving  movement,  or, 

1  "  The  phenomenon  finds  its  explanation  in  the  fact  that  first  one 
and  then  another  side  of  the  organ  elongates  more  rapidly  than  the 
rest.  If  this  takes  place  alternately  on  two  opposite  sides,  the  apex 
therefore  bends  over  at  one  time  to  the  left,  at  another  to  the  right ;  but 
if  at  the  circumference  of  the  organ  different  sides  in  succession  gradu- 
ally take  their  turns  in  the  process,  then  the  pendent  apex  must  rotate 
in  space." — Sachs,  "Lectures  on  the  Physiology  of  Plants,"  p.  546. 


FIG.  34.     MORNING- 
GLORY. 


124  CLIMBING    PLANTS. 

more  strictly  speaking,  of  the  continuous  bowing 
movement,  directed  successively  to  all  points  of 
the  compass,  is,  as  Mohl  has  remarked,  to  favor 
the  shoot  finding  a  support.  This  is  admirably 
effected  by  the  revolutions  carried  on  night  and 
day,  a  wider  and  wider  circle  being  swept  as  the 
shoot  increases  in  length.  This  movement  like- 
wise explains  how  the  plants  twine,  for  when  a 
revolving  shoot  meets  with  a  support,  its  motion 
is  necessarily  arrested  at  the  point  of  contact,  but 
the  free  projecting  part  goes  on  revolving.  As  this 
continues,  higher  and  higher  points  are  brought 
into  contact  with  the  support  and  are  arrested, 
and  so  onwards  to  the  extremity ;  and  thus  the 
shoot  winds  round  its  support.  When  the  shoot 
follows  the  sun  in  its  revolving  course,  it  winds 
round  the  support  from  right  to  left,  the  support 
being  supposed  to  stand  in  front  of  the  beholder ; 
when  the  shoot  revolves  in  an  opposite  direction, 
the  line  of  winding  is  reversed.  As  each  internode 
loses  from  age  its  power  of  revolving,  it  likewise 
loses  its  power  of  spirally  twining." 

Darwin  tried  experiments  with    many  twiners. 
In  the  case  of  one  plant  (Ceropegia  Gardnerii}  the 

1  "The  Movements  and  Habits  of  Climbing  Plants."     By  Charles 
Darwin.     D.  Appleton  &  Co.     1888.     p.  14. 


CLIMBING    PLANTS.  125 

revolving  shoot  was  31  inches  long.  "  The  extreme 
tip  thus  made  a  circle  of  above  5  feet  (or  62  inches) 
in  diameter  and  16  feet  in  circumference,  travel- 
ling at  the  rate  of  32  or  33  inches  per  hour.  The 
weather  being  hot,  the  plant  was  allowed  to  stand 
on  my  study-table ;  and  it  was  an  interesting  spec- 
tacle to  watch  the  long  shoot  sweeping  this  grand 
circle,  night  and  day,  in  search  of  some  object 
round  which  to  twine."  1 

Most  twiners  move  around  in  the  contrary  direc- 
tion from  the  hands  of  a  watch,  but  a  few  move 
from  the  left  to  the  right  of  the  observer.  In  rare 
cases  the  direction  may  reverse  in  the  same  plant. 
This  reversal  happens  frequently  with  leaf-climbers. 
Tropceolum  (Garden  Nasturtium)  is  a  good  example 
of  this  class  of  plants,  where  the  petioles  of  the 
leaves  clasp  the  support  (Fig.  35).  The  young 
shoots  of  leaf-climbers  revolve  like  the  stems  of 
twiners,  and  in  some  cases  the  leaves  revolve  also. 
"  The  object  gained  by  the  revolving  movement  is 
to  bring  the  petioles,  or  the  tips  of  the  leaves,  into 
contact  with  surrounding  objects  ;  and  without  this 
aid  the  plant  would  be  much  less  successful  in 
climbing.  With  rare  exceptions,  the  petioles  are 
sensitive  to  contact  only  whilst  young.  .  .  .  They 

.  i  "  Climbing  Plants,"  p.  6. 


126  CLIMBING    PLANTS. 

always  bend  towards  the  side  which  is  pressed  or 
touched,  at  different  rates  in  different  species, 
sometimes  within  a  few  minutes,  but  generally 
after  a  much  longer  period.  After  temporary 
contact  with  any  object,  the  petiole  continues  to 
bend  for  a  considerable  time ;  afterwards  it  slowly 
becomes  straight  again,  and  can  then  re-act.  A 


FIG.  35.     TROP/EOLUM    MINUS.     (Sachs). 

petiole,  excited  by  an  extremely  slight  weight,  some- 
times bends  a  little,  and  then  becomes  accustomed 
to  the  stimulus,  and  either  bends  no  more,  or  be- 
comes straight  again,  the  weight  still  remaining 
suspended.  Petioles  which  have  clasped  an  object 
for  some  little  time  cannot  recover  their  original 
position.  After  remaining  clasped  for  two  or  three 
days  they  generally  increase  much  in  thickness, 


CLIMBING    PLANTS.  127 

either  throughout  their  whole  diameter,  or  on  one 
side  alone  ;  they  subsequently  become  stronger  and 
more  woody,  sometimes  to  a  wonderful  degree ; 
and  in  some  cases  they  acquire  an  internal  struc- 
ture like  that  of  the  stem  or  axis."  l 

In  one  species  of  Tropceolum  examined  by  Dar- 
win the  first  young  leaves  were  like  tendrils,  with- 
out anything  resembling  a  leaf-blade.  As  the 
plant  grew  older  it  produced  these  tendril-like 
filaments  with  enlarged  tips,  then  with  partly 
formed  blades,  and  finally  with  perfect  leaves. 
The  filaments,  as  well  as  the  perfect  leaves,  were 
very  sensitive,  and  they  moved  spontaneously  and 
contracted  spirally,  as  do  perfect  tendrils.  The 
plant  would  be  called  a  tendril-bearer  if  it  acted 
in  this  way  when  mature ;  but  when  full-grown  it 
is  a  true  leaf-climber.  This  shows  us  very  plainly 
that  tendrils  are  modified  leaf-stalks.  They  may 
also  be  formed  from  modified  branches  or  flower- 
stalks. 

Plants  with  tendrils  are  wonderfully  interesting 
in  their  perfect  adaptation  for  purposes  of  climb- 
ing. The  tendrils  sweep  round  and  round,  and 
when  they  come  in  contact  with  a  support,  their 
sensitiveness  to  pressure  makes  them  bend  towards 

.!  "  Climbing  Plants/'  p.  81. 


128  CLIMBING    PLANTS. 

the  object  and  clasp  it.  Then  they  begin  to  con- 
tract into  a  spiral,  thus  dragging  the  stem  of  the 
plant  nearer  to  the  support,  and  allowing  other 
tendrils  to  grasp  it  also.  The  twist  is  in  one  direc- 
tion for  a  number  of  turns,  and  then  is  reversed, 
so  that  the  strain  is  not  too  great  (Fig.  36).  Be- 
sides bringing  the  shoot  near  its  support,  the  spiral 
contraction  is  useful  as  rendering  the  tendrils  elas- 
tic. "It  is  this  elasticity  which  protects  both 
branched  and  simple  tendrils  from  being  torn  away 
from  their  supports  during  stormy  wea-ther.  I 
have  more  than  once  gone  on  purpose,  during  a 
gale,  to  watch  a  Bryony,  growing  in  an  exposed 
hedge,  with  its  tendrils  attached  to  the  surround- 
ing bushes ;  and  as  the  thick  and  thin  branches 
were  tossed  to  and  fro  by  the  wind,  the  tendrils, 
had  they  not  been  excessively  elastic,  would  in- 
stantly have  been  torn  off  and  the  plant  thrown 
prostrate ;  but,  as  it  was,  the  Bryony  safely  rode 
out  the  gale,  like  a  ship  with  two  anchors  down, 
and  with  a  long  range  of  cable  ahead  to  serve  as 
a  spring  as  she  surges  to  the  storm  [Fig.  36]." 1 

When  a  tendril  finds  no  support,  it  contracts 
into  a  spiral  coil,  and  as  the  end  is  free  the  turns 
are  all  in  the  same  direction  (Fig.  36).  In  this 

1  "Climbing  Plants,"  p.  164. 


CLIMBING    PLANTS.  129 

case  it  soon  withers  ;  but  if  it  has  been  able  to  take 
hold  of  any  support,  it  becomes  firmer  and  stouter 


FIG.  36.     WHITE    BRYONY  (Bryonia  dioica).     (Sachs.) 

than  before.    If  it  does  not  clasp  anything,  it  curls 
up  into  a  simple  spire  and  gradually  withers  away. 


130  CLIMBING    PLANTS. 

One  of  the  strangest  things  about  tendrils  is 
that  they  do  not  often  clasp  each  other.  Although 
they  are  so  sensitive  to  contact,  they  do  not  move 
when  rubbed  with  other  tendrils.  Darwin  says 
about  the  Echinocystis  :  "  One  of  my  plants  bore 
two  shoots  near  together,  and  the  tendrils  were 
repeatedly  drawn  across  one  another,  but  it  is  a 
singular  fact  that  they  did  not  once  catch  each 
other.  It  would  appear  as  if  they  had  become 
habituated  to  contact  of  this  kind,  for  the  pressure 
thus  caused  must  have  been  much  greater  than 
that  caused  by  a  loop  of  soft  thread  weighing  only 
the  one-sixteenth  of  a  grain."  l 

Nor  do  the  tendrils  often  clasp  the  stem.  When 
a  tendril,  revolving  horizontally,  reaches  the  part 
of  its  course  where  it  would  strike  the  stem  of  the 
plant,  it  rises  vertically  upward,  becomes  stiff,  and 
so  passes  the  stem,  when  it  droops  to  its  original 
position  and  continues  its  horizontal  course. 

The  tendrils  of  Virginia  Creeper  (Fig.  37)  make 
little  discs,  which  adhere  firmly  to  the  wall  or  tree 
on  which  the  vine  grows.  These  discs  probably 
secrete  a  kind  of  cement,  which  glues  them  firmly 
to  the  wall.  If  the  tendrils  do  not  become  at- 
tached to  anything,  they  soon  wither  and  drop 

1  "Climbing  Plants/'  p.  131. 


FIG.  37.     VIRGINIA     CREEPER   (Ampelopis  hederacea).     (Sachsr.) 


132  CLIMBING    PLANTS. 

off ;  but  when  the  discs  are  formed  and  attached, 
the  tendril  becomes  very  strong. 

"  Plants  become  climbers,  in  order,  as  it  may  be 
presumed,  to  reach  the  light,  and  to  expose  a  large 
surface  of  their  leaves  to  its  action  and  to  that  of 
the  free  air.  This  is  effected  by  climbers  with 
wonderfully  little  expenditure  of  organized  matter, 
In  comparison  with  trees,  which  have  to  support 
a  load  of  heavy  branches  by  a  massive  trunk. 
Hence,  no  doubt,  it  arises  that  there  are  so  many 
climbing  plants  in  all  quarters  of  the  world,  be- 
longing to  so  many  different  orders.  These  plants 
have  been  arranged  under  four  classes,  disregard- 
Ing  those  which  merely  scramble  over  bushes  with- 
<out  any  special  aid.  Hook-climbers  are  the  least 
•efficient  of  all,  at  least  in  our  temperate  countries, 
.and  can  climb  only  in  the  midst  of  an  entangled 
mass  of  vegetation.  Root-climbers  are  excellently 
adapted  to  ascend  naked  faces  of  rock  or  trunks 
<of  trees;  when,  however,  they  climb  trunks,  they 
are  compelled  to  keep  much  in  the  shade ;  they 
cannot  pass  from  branch  to  branch  and  thus  cover 
the  whole  summit  of  a  tree,  for  their  rootlets 
require  long-continued  and  close  contact  with  a 
steady  surface  in  order  to  adhere.  The  two  classes 
of  climbers  and  of  plants  with  sensitive  organs, 


CLIMBING    PLANTS.  133 

namely,  leaf-climbers  and  tendril-bearers  taken 
together,  far  exceed  in  number  and  in  the  perfec- 
tion of  their  mechanism,  the  climbers  of  the  two 
first  classes.  Those  which  have  the  power  of 
spontaneously  revolving  and  of  grasping  objects 
with  which  they  come  in  contact,  easily  pass  from 
branch  to  branch,  and  securely  ramble  over  a 
wide,  sunlit  surface."  l 

1  "  Climbing  Plants,"  p.  189. 


134         PROTECTION    OF    THE    GREEN    TISSUE 


XI. 

PROTECTION   OF  THE  GREEN    TISSUE    FROM    THE 
ATTACKS  OF  ANIMALS.1 

THE  cells  of  plants  contain  albuminoids  similar 
to  the  white  of  egg,  and  in  their  green  tissues  are 
formed  carbohydrates,  such  as  starch  and  sugar, 
which  are  easily  digestible.  What  wonder  that 
numberless  animals  find  this  green  tissue  a  very 
desirable  food  !  Many  animals,  as  is  well  known, 
live  entirely  at  the  expense  of  plants.  In  this 
respect  the  animal  and  vegetable  kingdoms  are 
hostile  to  each  other,  for  the  removal  of  all  the 
green  parts  of  the  plant  ensures  its  destruction,  if 
its  store  of  reserve  food  is  exhausted.  Hunger 
drives  grazing  animals  to  snatch  the  plants  unmer- 
cifully, and  thus  completely  destroy  them.  The 
beasts  cannot  foresee,  as  men  do,  that  if  the  plant 
be  robbed  of  all  its  green  organs  it  will  die,  and 
that,  consequently,  in  the  following  year,  their 
own  existence  will  be  imperilled  for  lack  of  food. 
Man  leaves  enough  of  the  plants  which  he  uses  to 

1  Condensed  extracts  from  "Pflanzenleben,"  Vol.  I.  p.  399. 


FROM  THE  ATTACKS  OF  ANIMALS.     135 

secure  their  growth  and  increase;  nay,  he  himself 
assists  their  growth,  and  protects  them  at  the  cost 
of  much  labor  from  the  attacks  of  animals.  But 
only  a  very  small  proportion  of  the  whole  number 
of  plants  are  thus  cared  for  by  man ;  the  rest,  from 
which  he  receives  no  advantage,  must  find  means 
to  protect  themselves,  or  perish.  These  means  of 
protection,  it  is  true,  are  all  defensive,  so  that  the 
relation  between  plants  and  animals  is  not  to  be 
compared  to  a  state  of  war,  but  rather  to  an  armed 
peace. 

Nevertheless  these  defences  are  often  dangerous 
to  the  assailant,  and  they  include  poisons  and 
corrosive  fluids,  as  well  as  sharp  weapons. 

It  is  mysterious  how  grazing  animals  suspect  the 
existence  of  poison  in  leaves.  Sometimes  poison- 
ous plants  have  a  strong  odor  which  is  disagreea- 
ble to  men,  as  is  the  case  with  the  Thorn-Apple 
(Datura  Stramonium)-,1  but  many  others,  which 
are  equally  shunned  by  animals,  have  leaves  which 
are  scentless  to  us,  as  long  as  they  are  unbruised, 
like  the  Aconite,  the  Euphorbia,  and  the  Gentians, 
which  are  never  eaten  by  wild  animals,  nor  by 
grazing  flocks  and  herds.  As  long  as  they  remain 

1  A  good  American  example  is  the  Skunk  Cabbage  (Symplocarpus 
fuetidus') . 


136          PROTECTION    OF    THE    GREEN    TISSUE 

uninjured  in  field  and  wood,  they  have  no  odor 
perceptible  to  man;  but  animals  must  recognize 
these  plants  by  the  sense  of  smell,  before  they 
have  bitten  and  injured  them. 

That  the  green  leaves  of  the  Rhododendrons 
and  Azaleas,  of  the  Partridge-Berry,  the  Bearberry, 
and  of  many  other  low  evergreen  plants,  which 
form  a  large  part  of  the  vegetation  of  pastures 
and  moors,  as  well  as  of  the  high  mountain  slopes, 
are  avoided  by  grazing  animals  is  explained  by  the 
fact  that  they  are  indigestible,  owing  to  their  tough 
skin,  often  containing  silica.  It  is  certain  that  the 
formation  of  a  thick  arid  hard  cuticle,  and  the  pres- 
ence of  silica  in  the  epidermis  is  a  means  of  protec- 
tion against  grazing  animals,  by  which,  of  course, 
we  do  not  mean  to  say  that  this  structure  has  no 
other  function. 

Water  is  another  excellent  means  of  defence  for 
many  plants.  The  water  which  is  collected  by 
certain  leaves  from  the  rain  and  dew  often  remains 
in  special  receptacles  for  days  and  weeks.  Rumi- 
nating animals  do  not  graze  in  the  morning  when 
the  grass  is  covered  with  dew,  they  wait  till  the 
cold  drops  are  dried  up,  and  even  later  in  the 
day  they  avoid  those  plants  on  which  drops  are 
hanging. 


FROM  THE  ATTACKS  OF  ANIMALS.     13? 

But  the  most  important  means  of  defence  to  the 
plant  against  hungry  animals  are  organs  which  run 
out  into  sharp,  protruding  points,  ready  to  wound 
an  aggressor.  We  may  call  these  the  weapons  of 
the  plant.  They  may  be  divided  botanically  into 
thorns  and  prickles.  A  thorn  is  an  organ  which 
runs  out  into  a  sharp  spine,  composed  principally 
of  woody  tissue,  or  traversed  by  fibrovascular  bun- 
dles. A  prickle  is  an  outgrowth  from  the  skin  of 
a  plant,  without  woody  bundles,  one-celled  or  many- 
celled,  always  ending  in  a  sharp  point,  capable  of 
wounding  an  assailant.  This  distinction  is  not  an 
important  one  and  cannot  always  be  maintained. 

Spines  and  prickles  appear  on  every  possible 
portion  of  a  plant.  They  are  generally  above  or 
near  the  green  tissue  which  they  protect,  but  often 
the  path  leading  to  the  green  parts  over  leaf- 
stalks, stem,  and  sometimes  aerial  roots,  is  pro- 
vided with  prickles  and  thorns,  in  order  to  keep 
off  the  crawling  creatures  that  eat  the  leaves, 
especially  the  snails.  The  lower  parts  of  the  stem 
up  which  they  must  climb  to  reach  the  green  tissue 
are  armed  with  thorns  and  prickles  in  many  plants, 
as  in  Locusts  and  Roses. 

It  is  a  very  interesting  fact  that  many  woody 
plants  are  armed  only  while  they  are  low,  and 


138          PROTECTION    OF    THE    GKEEN    TISSUE 

their  leaves  can  be  reached  by  grazing  animals. 
As  soon  as  their  twigs  and  branches  are  out  of 
reach  of  the  jaws  of  the  beasts,  they  develop  no 
thorns.  The  Holly  is  an  example  of  this.  The 
leaves  which  deck  the  crown  of  the  high  tree- 
trunks  are  entire  and  unarmed,  while  on  the  low 
shrubs  the  margin  of  the  leaves  is  drawn  out  into 
sharp,  spiny  teeth.1 

We  may  divide  the  weapons  of  the  plant  into 
two  classes,  the  first  of  which  includes  the  forms 
where  the  green  tissue  is  protected  by  thorns  and 
prickles  developed  on  the  green  parts  themselves ; 
and  the  second,  those  where  other  portions  of  the 
plant  are  turned  into  arms  to  defend  the  unarmed 
green  parts. 

To  the  first  class  belong  those  leafless  plants 
which  have  developed  green  tissue  in  their  stems 
and  twigs.  It  is  true  that  the  green  branches  of 

1  This  is  the  subject  of  a  little  poem  by  Southey  :  — 

"  O  Reader!  hast  thou  ever  stood  to  see 

The  Holly-tree? 
The  eye  that  contemplates  it  will  perceive 

Its  glossy  leaves; 

Ordered  by  an  Intelligence  so  wise 
As  might  confound  an  atheist's  sophistries. 
Below,  a  circling  fence,  its  leaves  are  seen 

Wrinkled  and  keen; 
No  grazing  cattle  through  their  prickly  round 

Can  reach  to  wound; 

But,  as  they  grow  where  nothing  is  to  fear, 
Smooth  and  unarmed  their  pointless  leaves  appear." 


FROM  THE  ATTACKS  OF  ANIMALS.     139 

these  plants  are  so  stiff  and  hard  that  we  should 
hardly  think  they  would  tempt  animals  to  eat 
them.  But  "Hunger  is  a  stern  master,"  and  expe- 
rience shows  that  they  are  eaten.  Not  to  be  wholly 
at  the  mercy  of  such  attacks,  these  leafless  green- 
stemmed  plants  are  often  armed,  especially  by  the 
ends  of  their  green  branches  running  out  into 
spines,  bristling  against  the  assailant.  Indeed, 
many  of  these  plants  are  built  up  wholly  of 
many-branched  green  thorns,  which  gives  them  a 
very  singular  appearance. 

But  the  weapons  formed  on  leaves  are  far  more 
numerous  than  those  with  which  green  stems  are 
provided.  Sometimes  sharp  points  proceed  from 
the  ends  of  the  ribs  and  veins  which  make  the  leaf 
framework ;  sometimes  they  are  formed  of  cells  or 
groups  of  cells  which  originate  in  the  epidermis 
of  the  leaf  and  stand  out,  now  from  the  surface, 
now  from  the  margin,  like  little  daggers. 

In  the  Southern  Alps  is  found  a  species  of  grass 
(Festuca  alpestris),  growing  in  some  places  very 
abundantly.  Its  stiff  leaves,  which  stand  out  in 
every  direction,  end  in  sharp  points.  This  grass 
is  more  hated  than  any  plant  in  the  whole  region, 
and  the  shepherds  try  to  destroy  it  wherever  it 
grows  in  any  quantity.  Grazing  animals  seeking 


140          PROTECTION    OF    THE    GREEN    TISSUE 

other  plants  among  the  sods  of  Festuca  alpestris, 
often  prick  themselves  so  severely  that  they  come 
home  from  the  pasture  with  their  noses  all  running 
with  blood.  It  is  curious  that  when  such  grasses 
are  easily  uprooted  the  sheep  themselves  undertake 
their  destruction. 

Another  bristly  grass  (Nardus  stricta),  when  it 
grows  on  the  heaths,  is  pulled  out  of  the  ground 
by  the  sheep,  who  seize  the  clods  near  the  ground, 
uproot  them,  and  again  let  them  fall,  so  that  the 
grass  soon  withers  and  dies.  It  is  absurd  to  sup- 
pose that  the  flocks  undertake  with  forethought 
this  improvement  of  their  pasture,  but  we  can 
understand  that  they  may  pull  up  the  bristly  grass 
in  order  to  enjoy  the  other  sprouting  plants  beneath 
it,  without  the  danger  of  wounding  their  mouths 
with  the  sharp  points.  .  .  . 

Another  form  of  leaf  armed  with  spines  is  that 
belonging  to  the  Thistles  and  their  allied  forms. 
Thistle  leaves  are  often  three,  four,  or  five-divided, 
and  variously  incised  and  lobed.  If  the  ends  of 
all  these  divisions  are  metamorphosed  into  sharp 
points,  little  is  left  of  the  green  tissue  of  the  leaf; 
:only  a  small  green  space  remains  in  the  centre, 
from  which  yellow  and  white  thorns  stand  out  on 
every  side  (Fig.  38). 


FROM  THE  ATTACKS  OF  ANIMALS.     141 


FIG.  38.     GROUP   OF   THISTLES   (Cirsium  nemorale).     ("  Pflanzenleben.") 


142          PROTECTION    OF    THE    GREEN    TISSUE 

The  prickly  organs ,  which  are  not  to  be  regarded 
as  metamorphosed  ribs,  but  which  originate  in  the 
epidermis  of  the  leaf,  are  sometimes  many-celled, 
sometimes  one-celled.  One  form  of  the  one-celled 
prickles  are  barbs,  formed  of  oblique  conical  cells, 
which  stand  out  from  the  margin  of  the  leaf. 
They  end  in  a  firm,  hard  point,  which  is  usually 
somewhat  hooked  (Fig.  39,  7,  8).  Leaves  with 
their  margins  thickly  covered  with  such  barbs  look 
like  a  saw  under  the  microscope,  and  they  are  really 
able  under  some  circumstances  to  act  like  a  saw. 
If  we  stroke  one  of  these  barbed  leaves  very  gently 
from  the  side  towards  which  the  barbs  point,  they 
do  not  cut  into  the  opposing  hand,  but  they  also 
do  not  bend,  but  make  a  firm  resistance.  With 
increased  pressure  of  the  hand,  the  leaf  itself  is 
bent,  but,  as  this  is  also  well  stiffened,  the  pressing 
hand  experiences  a  resistance  which  would  not  be 
expected  from  so  tender  a  leaf.  If  the  hand  is 
passed  violently  over  the  sharp  margin,  a  bloody 
cut  is  made,  in  which  the  flinty  teeth  act  precisely 
like  the  teeth  of  a  fine  saw.  It  is  natural  that 
grazing  animals  should  shun  these  sharp  leaves, 
and,  in  fact,  they  only  eat  them  under  great  stress 
of  hunger. 

Another  form  of  arms,  which  has  its  origin  in 


FROM  THE  ATTACKS  OF  ANIMALS.     143 

the  cells  of  the  epidermis,  consists  of  stiff  hairs,  or 
bristles,  with  thick,  siliceous  cell-walls,  and  sharp 
points.  They  arise  generally  in  great  numbers  on 


FIG.  39.     WEAPONS   OF   PLANTS. 

3.  Section  through  a  Leaf  of  Nettle  (Urtica  dioica),  provided  with  Stinging  Hairs.  6.  Bristle 
of  the  Bugloss  (Echium  Italicum).  7.  Margin  of  the  Scabrous  Leaf  of  a  Sedge  (Carex 
stricta).  8.  Margin,  beset  with  Barbs,  of  a  Leaf  of  a  Scabrous  Grass  (Festuca  arundi- 
nacea).  ("  Pflanzenleben.") 

the  upper  surface  of  the  green  leaves,  and  turn 
their  points  towards  the  side  from  which  an  attack 
is  to  be  expected.  In  comparison  with  the  barbs 


144         PROTECTION    OF    THE    GREEN    TISSUE 

they  are  large;  for  even  the  smallest  is  much 
larger  than  these,  and  the  largest  look  like  needles 
with  their  heads  buried  in  the  leaf.  The  bristle 
itself  is  formed  of  a  single  cell,  which  is  on  a  sort 
of  pedestal  of  regularly  arranged  cells,  surround- 
ing its  base.  The  wall  of  this  long  cell  is  hard- 
ened by  deposits  of  silica,  and  often  thickened 
by  little  knots  (Fig.  39,  6).  The  Borrage  family 
is  provided  with  this  form  of  bristles,  as  may  be 
seen  in  the  Bugloss  (Echium),  the  Comfrey  (Sym- 
phytum),  etc. 

A  very  peculiar  form  of  protection  against  the 
attacks  of  larger  plant-eating  animals  is  the  pos- 
session of  stinging  hairs,  which  may  be  seen  on 
the  leaves  of  Nettles  and  some  other  plants. 
These  are  formed  of  large  cells,  like  the  sharp 
bristles  of  the  Borrage,  round  and  enlarged  below, 
and  long-drawn-out  above.  The  top  is  generally 
enlarged  and  bent  in  the  form  of  a  knee  (Fig. 
39,  3).  Here  the  cell-wall  of  the  hair  is  very 
thin,  so  that  the  smallest  pressure  is  able  to 
break  it.  As  the  breaking  follows  an  oblique 
line,  a  sharp  point  is  made.  If  this  brittle  end 
of  the  hair  is  shattered  by  a  pressure  from  above, 
the  sharp  point  formed  at  the  place  of  breaking 
presses  into  the  opposing  body ;  if  this  be  soft  and 


FROM  THE  ATTACKS  OF  ANIMALS.     145 

yielding,  like  the  skin  of  man  and  beasts,  the 
cell-contents  are  poured  into  the  wound.  If  many 
stinging  hairs  side  by  side  be  pressed  into  the  skin, 
there  follows  redness,  swelling,  and  violent  pain, 
from  the  poison  contained  in  the  cells.  Grazing 
animals  avoid  plants  with  stinging  hairs  most 
carefully. 

All  the  plants  which  we  have  mentioned  belong 
to  the  group  of  forms  where  the  green  tissue  itself 
possesses  its  weapons  of  defence.  With  this  group 
we  may  contrast  another  where  the  defences  are 
formed  by  neighboring  members  of  the  plant.  To 
this  second  group  belong  those  plants,  the  side 
branches  of  which  are  metamorphosed  into  woody 
thorns,  which  protect  the  unarmed  leaves  from 
attack.  The  stem  and  branches  of  these  plants 
are  not  leafy  to  their  ends.  If  there  is  any  trace 
of  leaves  on  the  ends  of  the  branches,  they  are 
small,  scaly,  and  anything  but  an  attractive  food. 
The  end  of  the  woody  branch  is  sharp  and  runs 
out  into  a  pointed  thorn.  Here  the  work  of 
defence  is  carried  on  by  a  division  of  labor.  The 
green  leaves  can  carry  on  their  office  undisturbed, 
under  the  protection  of  the  thorns.  An  example  of 
this  may  be  seen  in  Cytisus  spinosus  (Fig.  40,  5).1 

1  A  plant  belonging  to  the  same  genus  as  the  cultivated  Laburnum. 


146         PROTECTION    OF    THE    GREEN    TISSUE 


FIG.  40. 

4.   Robinia  Pseudacacia  in  Spring.     5.  Cytisus  spinosus.     6,  7.   Berberis  vulgaris  (Barberry) 
in  Spring.     ("  Pflanzenleben.") 


FROM  THE  ATTACKS  OF  ANIMALS.     147 

In  the  Barberry  (Berberis  vulgaris),  there  are 
two  kinds  of  leaves,  the  foliage  leaves  and  others 
which  are  not  leaf-like  at  all,  but  are  completely 
converted  into  sharp  thorns.  These  are  grouped 
in  five  to  seven  needle-like  points  at  the  base  of 
the  branch ;  higher  up  they  are  in  groups  of  three 
(Fig.  40,  6,  7).  Contemporary  with  these  meta- 
morphosed leaves,  and  close  above  them,  arise 
short  shoots,  which  are  covered  with  ordinary 
green  leaves.  These  shoots  are  terminated  by 
buds,  which  develop  in  the  next  spring  and  form 
either  flowers  or  a  long  shoot.  The  leaves  of  the 
rosette  under  this  bud  fall  in  the  autumn;  the 
thorns  at  the  base  remain  behind,  together  with 
the  winter  buds,  and  stand  out  from  the  branch  in 
three  directions  with  their  three-forked  needles. 
In  the  following  spring,  when  the  terminal  buds 
swell  and  expand,  the  tender  young  leaves  are 
well  protected  from  attack,  during  the  time  that 
they  are  overtopped  by  the  thorns. 

In  the  common  Locust-Tree  (Eobinia  Pseu- 
dacacia),  the  whole  leaves  are  not  metamorphosed 
into  thorns,  as  in  the  Barberry,  but  only  the  stip- 
ules. These  are  not  leaf-like,  but  are  triangular, 
sharp,  brown  thorns.  When  the  leaf  falls  in 
autumn  these  metamorphosed  stipules  remain 


148         PROTECTION    OF    THE    GREEN    TISSUE. 

behind,  and  last  through  the  winter  and  even 
through  the  following  summer.  In  the  niche 
between  these  stipules,  which  make  with  each 
other  an  angle  of  120°!,  nestles  the  bud,  which 
unfolds  in  the  following  spring.  As  long  as  the 
tender  young  leaves  remain  in  the  niche  between 
the  thorny  stipules  (Fig.  40,  4),  they  are  carefully 
shunned  by  animals ;  and  only  when  they  have 
grown  beyond  these  thorny  points,  does  this  pro- 
tection come  to  an  end. 

Most  of  these  protective  contrivances  only  pro- 
tect the  green  leaf  while  it  is  in  a  young  state. 
But  it  is  just  at  this  time  that  defence  is  most 
needful.  If  single  leaves  which  project  beyond 
the  thorns  are  eaten,  a  part  of  the  leaves  remain, 
and  the  loss  is  not  of  much  importance. 


One  extremely  curious  means  of  defence  is  not 
mentioned  in  the  foregoing  article.  Certain  plants 
secrete  a  nectar  which  is  very  attractive  to  black 
ants,  who,  therefore,  take  up  their  abode  upon 
these  plants,  and  constitute  a  sort  of  standing 
army,  ready  to  resist  furiously  the  onslaughts 
of  leaf-cutting  ants,  of  caterpillars,  and  even  of 
the  larger  animals. 


TRANSPIRATION.  149 


XII. 

TRANSPIRATION.1 

TRANSPIRATION  means  the  evaporation  of  water 
from  a  plant.  Let  us  imagine  a  plant  which  con- 
tains as  much  water  as  it  is  capable  of  holding, 
and  is  in  contact  with  an  available  supply  of 
water  in  the  ground.  Each  cell  contains  its  full 
amount  of  liquid,  and,  if  no  water  is  lost,  no  water 
will  be  absorbed  by  the  plant.  But  now  suppose 
that  evaporation  begins  to  take  place  from  the 
cells  which  are  in  contact  with  the  atmosphere. 
As  the  cell-walls  allow  liquids  to  pass  freely,  these 
cells  immediately  begin  to  draw  on  the  water  sup- 
ply of  their  neighbors,  and  these,  in  turn,  on  the 
cells  adjoining  them,  and  so  on,  till  throughout 
the  whole  plant  there  is  an  ascent  of  water  to 
supply  the  place  of  what  has  been  lost.  Finally 
the  call  is  made  on  the  rootlets,  and  these  promptly 
answer  the  demand  by  sucking  in  the  needed  liquid 

1  In  compiling  this  article  the  editor  has  availed  herself  largely  of 
the  charming  chapters  on  transpiration  in  "  Pflanzenleben."  The  book 
contains  many  interesting  suggestions  on  this  subject,  besides  those 
which  are  given  here. 


150  TRANSPIRATION. 

from  the  surrounding  earth.  Suppose  this  evapo- 
ration into  the  air  to  be  continuous,  and  we  have 
a  constant  stream  of  water  flowing  from  the 
damp  earth,  through  roots  and  rootlets,  stem 
and  branches,  to  the  leaves.  This  is  what  actu- 
ally does  take  place,  and  this  stream  is  known 
as  the  transpiration  current. 

But  roots  do  not  absorb  water  alone.  The 
delicate  hairs,  —  outgrowths  of  the  skin, — which 
clothe  thickly  all  their  young  parts,  give  out  an 
acid  which  can  dissolve  the  mineral  matters  in 
the  soil.  It  is  not  certainly  known  what  this  acid 
is,  but,  whatever  it  may  be,  by  a  most  beautiful 
arrangement  it  dissolves  the  food  of  the  plant 
just  where  the  root-hairs  are  present  to  absorb 
it.  In  this  way  roots  are  able  to  disintegrate 
the  soil,  and  to  absorb  its  mineral  matters  in 
weak  solutions,  which  are  carried  all  over  the 
plant.  They  are  brought  in  the  way  we  have 
described  into  the  cells  communicating  with  the 
external  air,  where  they  are  greatly  concentrated 
by  the  escape  of  water,  and  are  then  ready  to  be 
converted  into  food.  This  is  done  by  the  action 
of  carbonic  acid  gas,  absorbed  from  the  air.  By 
means  of  this  gas  the  raw  mineral  material 
brought  from  the  ground  is  converted  into  or- 


TRANSPIRATION.  151 

ganic  matter,  the  food  of  plants  and  the  food  also 
of  animals. 

The  path  of  the  ascent  of  the  crude  sap  is 
through  the  woody  portions  of  the  plant.  The 
woody  tissues  of  the  roots  carry  the  water  from 
cell  to  cell  to  the  fibrovascular  bundles  of  the  stem ; 
it  then  rises  through  all  the  branches  and  twigs 
till  it  reaches  the  leaves.  Each  leaf  has  a  woody 
framework,  which  divides  again  and  again,  till  it 
makes  a  network  of  fibres,  on  which  the  green 
tissue  (parenchyma)  is  supported.  The  most  deli- 
cate fibrils  of  this  woody  framework  are  in  close 
contact  with  the  cells  of  the  leaf  which  communi- 
cate with  the  outer  air,  and  the  water  which  has 
been  brought  hither  from  the  roots  escapes  into 
the  atmosphere. 

We  can  see  that  it  must  be  the  wood  which  con- 
ducts the  water,  by  looking  at  old  trees,  whose 
trunks  are  hollow  and  whose  bark  has  also  been 
destroyed  around  the  base  of  the  tree.  This  is 
especially  striking  in  old  olive  trees,  which  often 
are  not  only  hollow  and  destitute  of  bark,  but  are 
pierced  and  broken,  so  that  the  upper  part  of  the 
tree  looks  as  if  it  were  mounted  on  stilts,  and  is 
only  connected  with  the  ground  by  woody  tis- 
sue. Yet  these  olive  trees  are  healthy,  bring  forth 


152  TRANSPIRATION. 

new  branches  every  year,  bloom,  bear  fruit,  and 
supply  their  wants  with  nourishment,  which  could 
have  come  to  them  in  no  other  way  than  through 
the  wood  of  their  scraped  and  hollow  trunks.1 

We  may  also  prove  that  the  crude  sap  rises 
through  the  woody  tissues  by  girdling  the  stem 
of  a  tree ;  that  is,  by  cutting  off  a  ring  of  bark 
without  injuring  the  wood.2  This  does  not  kill 
the  tree,  as  may  be  seen  in  birch  trees  which  have 
been  girdled  for  the  sake  of  the  bark.  But  if 
the  wood  be  cut  in  a  similar  ring  the  tree  will 
soon  die.  Most  of  the  water  in  a  tree  is  carried 
up  in  the  outermost  layer  of  wood,  just  under 
the  bark. 

When  the  water  reaches  the  leaves  and  is  carried 
through  the  ribs  and  veins  into  the  cells  of  the 
parenchyma  of  the  leaf  blade,  it  cannot  escape 
into  the  air  to  any  extent  through  the  cell-walls 
of  the  epidermis,  because  their  outer  walls  have 
been  thickened  and  made  waterproof.  But  the 
leaves  are  pierced  by  openings,  connecting  with 
the  external  air,  through  which  water-vapor  can 
escape  and  air  can  enter.  These  openings  are 

1  "  Pflanzenleben,"  Vol.  I.  p.  252. 

2  See   "Lectures    on  the   Physiology   of   Plants."     J.   von  Sachs. 
Trans,  by  H.  Marshall  Ward.      Oxford,  1887.    p.  229. 


TRANSPIRATION. 


153 


called  stomata  (Fig.  41).  They  are  formed  by  two 
cells,  called  guardian  cells,  with  a  narrow  slit  be- 
tween them,  which  they  have  the  power  to  open 


FIG.  41. 

I.  Stomata  on  a  Leaf  of  Peperomia  arifolia.       2.  Cross-Section  of  the  Same  Leaf. 
("  Pflanzenleben.") 

or  to  close.  Both  the  cells  are  shaped  like  a  half- 
moon,  with  the  concave  side  towards  the  slit  and 
the  convex  side  joining  the  neighboring  cells  of 
the  epidermis.  Beneath  the  opening  of  each  stoma 


154  TRANSPIRATION. 

is  an  air  space,  whence  the  air  can  pass  into  other 
cells  of  the  plant.  The  stomata,  therefore,  are  the 
breathing  pores  by  means  of  which  water  is  exhaled 
from  the  plant,  and  carbonic  acid  gas  is  inhaled. 
When  the  guardian  cells  absorb  water  they  swell, 
and  this  makes  them  curve  farther  apart  and 
widens  the  slit,  so  that  the  water  can  evaporate 
faster.  When  the  plant  begins  to  wilt,  which  is 
caused  by  a  collapsing  of  the  cell-walls  for  want 
of  sufficient  water,  the  guardian  cells  contract,  and 
this  closes  the  slit  and  checks  the  evaporation  of 
water,  so  that  most  of  the  liquid  brought  from  the 
roots  is  retained  within  the  plant.1  If  plenty  of 
water  be  again  supplied  to  the  plant  which  has 
begun  to  wilt,  it  will  recover  itself,  the  cells  again 
become  turgid,  the  stomata  open,  and  transpira- 
tion is  resumed. 

Stomata  open  more  widely  in  light  than  in 
darkness.  According  to  some  observers,  they  are 
always  open  in  sunlight.  This  will  explain  the 
reason  why  stomata  are  generally  more  numerous 
on  the  under  side  of  the  leaf.  Transpiration  would 
go  on  too  rapidly  if  they  were  exposed  to  the 
direct  rays  of  the  sun.  Where  the  leaves  are 

1  The  mechanism  is  too  complicated  for  further  explanation  here. 
See  Sachs,  "  Physiology  of  Plants,"  p.  249. 


TRANSPIRATION. 


155 


vertical  instead  of  parallel  with  the  ground,  the 
stomata  are  on  both  sides  of  the  leaf. 


FIG.  42.     COMPASS    PLANT    (Silphium    laciniatum), 
I.  Seen  from  the  East.     2.  Seen  from  the  South. 

An  excellent  example  of  this  is  the  Compass 
Plant  (Silphium  laciniatum,  Fig.  42)  of  the  Western 


156  TRANSPIRATION. 

prairies,  which  has  its  leaves  placed  vertically, 
with  the  edges  pointing  north  and  south,  so  that 
the  plant  is  said  to  guide  travellers  on  their  jour- 
neys across  the  prairie.1  At  morning  and  evening 
the  leaves  are  warmed  directly  by  the  sun's  rays, 
but  at  midday,  when  the  sun  is  hot  overhead,  the 
beams  fall  on  the  edges  of  the  leaves,  and  the 
plant  is  protected  from  too  great  transpiration. 
Young  leaves,  by  taking  a  vertical  position,  are 
protected  from  exposure  to  the  direct  rays  of  the 
sun.2 

The  leaves  of  plants  which  float  on  the  surface 
of  the  water,  as  the  Water  Lily,  have  their  stomata 
all  on  the  upper  side.  Submerged  water-plants 
have  no  stomata  at  all,  nor  are  the  outer  cells  of 
their  epidermis  waterproof.  They  transpire  from 
their  whole  surface,  and  this  is  the  reason  why  they 
collapse  so  immediately  when  they  are  taken  from 
the  water.  Their  food  is  all  about  them,  and  they 
have  no  need  for  such  a  complicated  arrangement 

1  Longfellow  mentions  this  in  "  Evangeline  " : 

"  Look  at  this  delicate  plant  that  lifts  its  head  from  the  meadow, 
See  how  its  leaves  all  point  to  the  north,  as  true  as  the  magnet; 
It  is  the  compass  flower,  that  the  finger  of  God  has  suspended 
Here  on  its  fragile  stalk  to  direct  the  traveller's  journey 
Over  the  sea-like,  pathless,  limitless  waste  of  the  desert." 

He  is  in  error,  however,  in  calling  the  plant  delicate. 

2  See  VIII.  "  Young  and  Old  Leaves,"  p.  84. 


TRANSPIRATION.  157 

for  pumping  it  up  from  the  roots  as  land-plants 
possess. 

The  stomata  are  of  course  a  great  deal  too  small 
to  be  seen  without  a  microscope,  but  there  is  a 
way  in  which  we  can  tell  on  which  side  of  any 
leaf  they  are  to  be  found.  Dip  the  leaf  in  water, 
and,  after  holding  it  there  for  some  time,  take  it 
out  and  shake  it.  Wherever  a  film  of  water 
covers  the  leaf,  there  are  no  stomata ;  but  where 
the  leaf  is  dry,  there  they  will  be  sure  to  be  found.1 
It  would  be  an  injury  to  the  plant  to  have  its 
breathing  pores  clogged  with  water.  Therefore 
the  surface  where  the  stomata  are  is  protected  in 
various  ways  from  the  wet.  Many  leaves  have 
what  we  call  "bloom"  upon  them.  This  is  a 
waxy  coating  which  prevents  the  rainwater  from 
adhering  to  the  leaves.  It  can  be  observed  on  the 
leaves  of  Cabbage,  Nasturtium,  Castor  Oil  Plant, 
Begonias,  and  Primroses.  The  beautiful  Gold  and 
Silver  Ferns  in  our  conservatories  have  the  lower 
side  of  their  leaves  covered  with  a  sort  of  yellow 
or  white  meal,  which  answers  the  same  purpose. 

Another  mode  of  protection  is  through  the  help 
of  hairs.  A  countless  number  of  leaves  of  our 
common  plants  are  covered  with  fine  hairs,  and 

i  •«  Pflanzenleben,"  Vol.  I.  p.  267. 


158  TRANSPIRATION. 

these  are  more  frequent  on  the  lower  sides  of  the 
leaves.  If  we  dip  these  leaves  in  water,  the  wet 
collects  in  the  form  of  drops,  which  roll  off  when 
the  leaf  is  shaken  and  leave  no  moisture  behind. 
It  might  be  thought  that  the  under  side  of  a  leaf 
would  be  protected  by  its  position  from  rain,  but 
if  we  turn  over  a  leaf  on  a  dewy  morning,  we 
shall  find  that  the  water  is  as  much  on  its  under 
as  its  upper  side.  We  forget,  when  we  speak  of 
the  falling  of  the  dew,  that  this  is  only  a  figure  of 
speech,  —  that  the  dew  is  really  condensed  just  as 
much  on  the  lower  as  on  the  upper  side  of  a  leaf. 

These  waxy  coverings  to  the  leaves  and  their 
garments  of  hair  prevent  excessive  evaporation, 
and  are  often  also  a  defence  against  the  attacks 
of  animals. 

Another  means  of  defence  is  the  occurring  of 
numberless  little  projections  all  over  the  surface 
of  the  leaf.  When  the  falling  drops  of  water  roll 
over  such  a  surface,  they  cannot  dislodge  the  air 
which  fills  the  depressions.  As  the  stomata  are 
always  in  these  pits,  they  are  kept  dry,  and  are 
not  wet  even  if  the  whole  plant  is  immersed  in 
water.  This  means  of  protection  is  common  with 
plants  growing  in  places  where  they  are  liable  to 
be  immersed  for  weeks  together,  as  with  some 


TRANSPIRATION,  159 

Grasses  (Glyceria  aquatica,  Phalaris  arundinacea), 
Sedges  (Carex  stricta),  and  Knot-weeds  (Polygonum 
ampliibium).  It  is  a  pretty  sight  to  see  one  of 
these  leaves  held  under  water.  The  whole  under 
surface  shines  like  quicksilver,  and  however  we 
may  shake  and  turn  the  leaf,  we  cannot  dislodge 
its  covering  of  air.  When  we  take  it  out  of  the 
water  this  side  of  the  leaf  is  quite  dry,  while  the 
other  is  wet.  Stomata  are  also  found  on  stems, 
but  they  are  not  so  numerous  as  on  leaves. 

Some  kinds  of  trees  may  have  a  great  effect  in 
transferring  water  from  the  soil  to  the  atmos- 
phere. The  Eucalyptus  tree  is  the  most  useful 
for  this  purpose,  and  is  often  planted  in  order  to 
drain  marshy  places. 


160  USES    OF    FORESTS    AND    OTHER 


XIII. 

USES  OF  FORESTS  AND  OTHER  PLANT  COVER'NG 
OF  THE  EARTH. 

BY  N.  S.  SHALER. 

THE  greater  part  of  the  land  surface  of  the 
earth  is  thickly  covered  with  growing  plants. 
Where  the  rainfall  is  sufficient  and  where  the 
region  is  exempt  from  wide-spread  fires,  such  as 
sweep  over  the  prairies  of  the  Mississippi  Valley, 
we  always  find  a  growth  of  forest  trees.  Where 
the  rainfall  is  scanty,  or  where  these  annual  confla- 
grations occur,  the  forests  are  replaced  by  grasses, 
or  other  low-growing  plants,  which  may  maintain 
their  roots  in  a  living  state  through  the  winter,  but 
have  no  permanent  growth  above  the  level  of  the 
soil.  Generally  speaking,  only  those  regions  where 
the  rainfall  is  less  than  about  ten  inches  a  year 
are  without  plant  covering  of  any  kind,  and  this 
area  is  but  a  small  part  of  the  surface  of  the 
earth. 

The  influence  of  this  coating  of  plants  on  the 
conditions  of  the  earth  is  very  important  in  many 


J>LANT    COVERING    OF    THE    EARTH.  161 

Ways.  We  will  consider  some  of  its  simpler  effects, 
paying  particular  attention  to  the  influences  which 
most  concern  man. 

The  most  immediate  effect  produced  by  forests 
is  the  improvement  of  the  soil  into  which  their 
roots  penetrate.  Wherever  trees  succeed  in  finding 
a  foothold  upon  the  surface  of  the  earth,  they  pro- 
ceed at  once  to  make  and  to  preserve  a  coating  of 
soil,  which  in  the  end  may  become  fit  for  cultivation. 
The  roots  penetrate  downward  into  the  crevices  of 
the  rock,  starting  as  slender  filaments  which,  grow- 
ing in  size,  wedge  the  stones  apart  and  thus  make 
the  beginnings  of  a  soil.  Into  every  cranny  of  the 
disrupted  stone,  yet  other  roots  find  their  way  and 
repeat  the  process  of  breaking.  In  this  way  in 
the  subsoil,  the  rock  is  fractured  into  bits,  becomes 
subjected  to  the  dissolving  action  of  the  soil  water, 
and  so  affords  food  for  plants.  As  long  as  the 
rock  remains  in  the  condition  of  a  solid  mass,  it 
can  yield  but  little  plant-food.  In  that  condition 
there  is  only  a  small  amount  of  surface  for  the 
water  to  work  upon.  If  we  break  a  cubic  foot  of 
that  rock  into  bits  a  cubic  inch  in  size,  we  multiply 
the  surface  exposed  to  solution  twelve-fold.  If 
these  bits  are  in  turn  divided  into  cubes  the 
twelfth  of  an  inch  on  a  side,  we  again  multiply 


162  USES    OF    FORESTS    AND    OTHER 

the  surface  exposed  to  the  water  by  an  equal 
amount;  and  when  we  come  down  to  the  fine 
grains  of  mud  which  in  time  are  made  from  the 
larger  fragments,  we  find  that  the  surface  of 
the  rock  from  which  the  waters  may  dissolve 
plant-food  is  increased  many  thousand  fold  by 
the  process  of  division.  The  root-hairs,  also, 
secrete  an  acid,  capable  of  dissolving  mineral  sub- 
stances with  which  they  are  in  contact,  and  this 
acid  fluid  aids  them  to  decompose  the  particles  of 
stone.  In  this  way  the  rootlets  of  the  plants  serve 
in  part  to  create  from  the  solid  rocks  the  soil  that 
gives  them  support.1 

Not  only  do  the  trees  help  to  make  the  soil  upon 
which  they  dwell,  but  they  also  preserve  it  from 
destruction.  If  the  reader  will  notice  any  tilled 
field  in  a  time  of  heavy  rain,  he  will  perceive  that 
the  soil  is  rapidly  borne  away  in  the  form  of  mud 
to  the  rivers  and  thence  to  the  sea.  If  he  will 
observe  such  a  piece  of  ground  after  a  heavy  rain, 

1  This  influence  of  plants  on  their  mineral  substratum  is  clearly  evi- 
dent where  Lichens  and  Mosses  attach  themselves  to  the  free  surfaces 
of  rocks,  e.g.,  on  high  mountains.  The  solid  crystalline  surface  of  the 
stone  becomes  gradually  converted,  by  the  activity  of  the  roots  of  these 
plants,  into  a  friable,  crumbling,  loose  substance.  This  decay  continu- 
ally penetrates  deeper  into  the  stone,  and  so  affords  a  substratum  in 
which  even  the  stronger  roots  of  larger  plants  can  then  obtain  a  hold. 
"  Lectures  on  the  Physiology  of  Plants."  Sachs. 


PLANT  COVERING  OF  THE  EARTH.     163 

lie  will  often  notice  flat  pieces  of  stone  or  potsherds 
resting  on  top  of  little  columns  of  soil.  From  this 
he  may  draw  the  conclusion  that  during  the  rain 
the  soil  has  washed  away  to  a  depth  equal  to  the 
height  of  the  column  on  which  the  flat  fragments 
rest.  In  fact,  they  have  protected  the  earth  imme- 
diately beneath  them  from  the  destruction  which 
the  rain  brings  about.  It  is  a  well-known  fact 
that  in  all  countries  where  the  soil  has  long  been 
tilled,  it  constantly  diminishes  in  depth  and,  unless 
great  care  is  taken,  in  a  few  centuries  it  passes 
away  into  the  streams,  only  remaining  where  the 
surface  is  very  level.  Thus  in  Italy  and  in  many 
of  the  countries  which  have  long  been  tilled,  the 
soils  on  the  steeper  slopes  which  once  were  fertile 
have  now  so  far  disappeared  that  many  extensive 
districts  are  given  over  to  sterility.1 


1  In  May,  1888,  a  new  forest  law  went  into  effect  in  Italy,  by  which 
the  government  pledged  itself  to  pay  three-fifths  of  the  cost  of  reforesta- 
tion of  the  mountain  districts,  the  rest  of  the  expense  to  be  met  by  the 
owners.  In  case  the  owners  do  not  consent  to  the  plan  prepared  by 
the  Department  of  Agriculture,  the  government  is  to  be  at  liberty  to 
take  the  land  with  proper  compensation  and  perform  the  work  alone. 
The  estimated  cost  of  the  plan  proposed  is  $12,000,000.  Such  enormous 
expense  in  the  near  future  can  be  spared  to  America  at  a  very  small 
cost  of  present  money  and  labor.  If  we  do  not  soon  take  some  more 
effective  means  than  at  present  to  preserve  our  forests  our  descendants 
will  have  to  follow  the  example  of  Italy  and  spend  millions,  where 
we  might  have  accomplished  better  results  with  thousands. 


164  USES    OF    FORESTS    AND    OTHER 

Forests  serve  not  only  to  prevent  the  wasting  of 
the  soil  under  the  pelting  influence  of  the  rain  but 
they  also  greatly  restrain  the  action  of  the  rivers, 
even  the  largest.  Thus  the  Mississippi  River  and 
other  similar  great  streams  are  restrained  in  the 
destruction  they  would  otherwise  bring  to  the  allu- 
vial plains  ort  either  side  of  their  current  by  the 
constant  growth  of  trees  which  line  the  banks. 
Willows,  Poplars,  and  certain  other  water-loving 
plants  thrive  along  the  banks  of  the  stream,  send 
their  roots  downward  beneath  the  surface  occupied 
by  the  flood-waters  and  so  make  a  strong  net-work 
which  resists  the  cutting  action  of  the  river  and 
keeps  the  stream  within  narrow  bounds.  Even  in 
our  brooks  where  they  flow  through  virgin  forests 
the  falling  trees  and  other  drift-wood  make  fre- 
quent dams  across  the  path  of  the  waters,  and  here 
the  soil  washed  from  the  highlands  is  retained, 
making  little  patches  of  earth. 

Forests  also  act  to  prevent  floods.  If  the  rain 
falls  on  an  unforested  country  the  water  flows 
quickly  over  the  bare  surface  to  the  brooks  and 
thence  to  the  larger  rivers  on  its  way  to  the  sea. 
In  such  a  region  the  rain  goes  away  to  the  ocean 
as  it  does  from  our  house  roofs  or  paved  streets. 
When,  however,  the  rain  falls  upon  the  forests, 


PLANT  COVERING  OF  THE  EARTH.     165 

the  water  enters  into  a  thick  spongy  layer,  com- 
posed of  partly  decayed  leaves  together  with  trunks 
and  branches  which  are  constantly  dropping  from 
the  trees  upon  the  surface  of  the  earth.  Through 
this  sponge  the  water  moves  but  slowly  on  its  way 
to  the  streams,  and  when  it  is  actually  in  the 
brooks  its  progress  downward  is  retarded  by  numer- 
ous dams  made  as  we  have  just  described  by  fallen 
timber  and  drift-wood.  The  result  is  that  instead 
of  pouring  swiftly  to  the  sea,  the  flood-waters  may 
slowly  creep  away,  requiring  weeks  in  place  of 
hours  for  their  discharge  to  the  greater  rivers. 

There  is  another  effect  which  forests  have  upon 
the  soil,  an  effect  which  is  not  exercised  by  any 
plants  less  in  size  than  our  trees.  The  strong 
roots  of  trees,  penetrating  far  down  into  the  crev- 
ices of  the  rocks  and  into  the  subsoil,  draw  upward 
above  the  surface  and  build  into  their  trunks  the 
solid  matter  which  we  find  in  the  ash  remaining 
after  the  wood  is  completely  burned.  This  valua- 
ble nutritive  matter  drawn  from  the  depths  is 
returned  to  the  earth  when  leaves  and  branches 
decay,  and  is  thus  stored  in  the  upper  part  of  the 
soil,  and  becomes  accessible  to  the  growing  crops. 
Furthermore  the  trees  in  their  growth  gather,  as  is 
the  case  with  all  plants,  a  large  part  of  their  sub- 


166  USES    OF    FORESTS    AXD    OTHER 

stance  from  the  air.  All  the  material  which  goes 
into  the  air  when  we  burn  wood  came  from  the 
atmosphere  during  the  growth  of  the  plant.  When 
the  tree  dies,  or  when  its  leaves  and  branches  fall 
in  the  perennial  death  of  its  parts  which  attends 
the  growth  of  the  whole  plant,  this  carbon  drawn 
from  the  atmosphere  is  more  or  less  built  into  the 
soil,  giving  it  the  blackish  look  which  is  always 
found  in  fields  recently  won  from  woodlands. 
This  mixture  of  decayed  vegetable  matter  serves 
in  several  important  ways  to  make  the  soil  fruitful. 
The  farmer  has  to  imitate  the  natural  process  which 
goes  on  in  the  forest  by  ploughing  in  clover,  buck- 
wheat, or  other  crops  in  order  to  introduce  the 
vegetable  matter  into  the  soil  and  so  maintain  its 
fertility. 

The  utility  of  forests  to  man,  though  best  exhib- 
ited in  the  processes  by  which  they  make,  save, 
and  enrich  the  soil,  is  shown  in  many  ways.  From 
the  forests  we  derive  the  construction  timber,  which 
constitutes  a  large  part  of  all  houses,  and  of  itself 
is  sufficient  for  the  greater  part  of  the  dwellings 
inhabited  by  man  ;  without  this  supply  hardly  one 
of  our  arts  could  be  maintained.  Even  in  our 
large  cities,  where  the  outer  walls  are  of  masonry, 
the  greater  part  of  the  structure  is  composed  of 


PLANT  COVERING  OF  THE  EARTH.     167 

wood.  So,  too,  timber  is  necessary  for  the  con- 
struction of  our  agricultural  machinery,  of  the 
greater  part  of  our  ships,  and  of  a  host  of  other 
structures  which  are  essential  to  the  well-being 
of  man.  In  the  present  state  of  our  arts,  we 
could  more  easily  give  up  all  the  other  resources 
drawn  from  the  earth,  except  perhaps  iron,  than 
forego  the  use  of  wood  from  our  civilization. 

Although  mineral  coal  has,  in  the  more  civilized 
parts  of  the  world,  to  a  great  extent  taken  the  place 
of  wood  for  heating  purposes,  probably  three-fourths 
of  the  domestic  hearths  in  the  world  are  supplied 
from  the  forests.  In  time  it  is  to  be  hoped  that 
the  use  of  stone  coal  will  become  yet  more  exten- 
sive, for  it  will  diminish  the  tax  which  is  made 
upon  the  woods,  and  so  spare  them  for  more 
necessary  uses. 

Among  the  uses  of  the  forests  we  must  include 
the  shelter  which  they  afford  to  human  beings,  and 
to  the  cattle  of  our  farms.  Where  the  country  is 
untimbered,  the  winds,  having  a  free  sweep  over 
the  surface  of  the  earth,  move  in  times  of  storm 
more  furiously  than  in  the  forests,  where  the  trees 
afford  a  most  important  shelter.  In  the  prairie 
districts  of  the  upper  Mississippi,  it  has  been  found 
necessary  to  plant  trees  about  the  homesteads  in 


168  USES    OF    FORESTS    AND    OTHER 

order  to  make  thefti  reasonably  habitable  during 
the  blizzards  and  to  shelter  the  stock. 

The  character  of  the  forests  varies  greatly  in 
different  parts  of  the  world.  The  noblest  woods 
of  the  earth  are  probably  those  of  North  America. 
The  district  of  the  Appalachians  from  Northern 
New  York  to  Alabama,  though  much  harmed  by 
the  woodsman's  axe  and  more  by  fires,  still  presents 
the  finest  areas  of  broad-leaved  trees  in  the  world. 
Individual  members  of  related  kinds  in  other  coun- 
tries may  be  nobler  specimens  of  growth,  but 
nowhere  else  are  the  -woods  so  continuous  and 
so  luxuriant  over  a  wide-spread  surface.  In  the 
western  parts  of  the  continent,  near  the  Pacific 
coast,  the  narrow-leaved  coniferous  trees  take  on 
a  lofty  growth.  The  great  Sequoias  or  Eedwoods 
of  California  are  probably  to  be  ranked  as  the 
noblest  plants  in  the  world,  being  only  approached 
in  size  by  some  of  the  great  trees  of  Australia, 
which  do  not,  however,  attain  the  same  majesty 
as  those  of  the  Pacific  coast. 

Where  trees  grow  in  the  close-set  order  of  the 
forest  they  attain  a  greater  height  than  in  the 
open  ground.  For  great  forests  have  been  devel- 
oped in  the  endeavor  of  each  tree  to  overtop  its 
neighbors  and  obtain  a  measure  of  the  sunshine, 


PLANT  COVERING  OF  THE  EARTH.     169 

without  access  to  which  the  plant  cannot  do  its 
best  work.  To  develop  a  forest  of  very  tall  trees 
demands  long  ages.  If  we  cut  a  wood  away  and 
permit  the  trees  to  grow  again,  they  will  develop 
with  much  shorter  stems  than  the  parent  wood. 
Only  slowly  does  the  forest  climb  again  to  its 
primeval  elevation.  Hence  it  comes  about  that 
the  forests  of  the  New  World  are  so  much  higher 
than  those  of  the  Old.  In  Europe  there  are  hardly 
any  woods,  at  most  but  scant  patches,  which  have 
escaped  the  axe.  Almost  all  the  timber  is  of  the 
second  growth. 

The  close  relation  of  forests  to  the  needs  of  man 
make  it  essential  that  in  any  country,  which  is  to 
be  kept  in  the  best  condition  for  human  occupa- 
tion, a  large  share  of  its  woodlands  should  be 
spared  destruction.  When  civilized  men  first 
came  to  this  country,  they  found  all  the  regions 
to  which  they  had  access  in  the  state  of  dense 
woods.  It  was  a  difficult  matter  to  clear  away 
these  forests  in  order  to  reduce  the  soil  to  the  uses 
of  the  plough.  Thus  the  farmers  have  got  into 
the  habit  of  looking  upon  the  woods  as  enemies  to 
be  driven  away.  The  result  of  this  is  that  the  de- 
struction of  the  forests  has  proceeded  with  great 
rapidity ;  indeed,  with  a  recklessness  which  jeop- 


rapidii 


170  USES    OF    FORESTS    AND    OTHER 

ardizes  the  interests  of  many  communities.  Thus, 
in  the  valley  of  the  Ohio,  the  rapid  destruction  of 
the  woods  now  necessitates  the  bringing  of  timber 
for  building  purposes  from  great  distances. 

In  almost  all  countries  a  portion  of  the  surface 
seems  marked  by  nature  as  the  fit  place  for  the 
growth  of  woods.  The  steep  mountain  slopes  or 
the  rocky  parts  of  the  lower  hills  which  are  not  by 
their  position  well  suited  to  the  growth  of  tillage 
crops  are  generally  admirable  places  for  forest  uses. 
Trees  will  not  only  grow  but  flourish  exceedingly 
on  slopes  so  steep  or  so  stony  that  they  are  unfit 
for  cultivation.  A  proper  economy  dictates  that 
all  such  regions  should  be  left  in  their  original 
forest  condition,  or  if  they  have  been  recklessly 
cleared  away,  that  trees  should  be  replanted  upon 
them. 

Last  of  all,  we  may  note  the  elements  of  beauty 
which  are  afforded  by  our  woods.  None  accus- 
tomed to  dwell  near  pine  trees  or  within  accessible 
distances  of  the  primeval  forest  has  any  idea  how 
important  are  these  elements  in  the  landscape.  If 
he  will  dwell  awhile  on  the  prairies,  where  trees 
are  found  only  near  the  larger  streams,  and  there, 
indeed,  in  scanty  growth,  he  will  soon  come  to 
recognize  that  the  beauty  of  the  woods  is  in  a  way 


PLANT  COVERING  OF  THE  EARTH.     171 

essential  to  him,  and  he  thus  can  measure  how 
great  is  his  enjoyment  in  the  sight  of  forests. 

The  woods  not  only  afford  a  noble  life  in  their 
own  trees,  but  they  supply  a  place  for  the  protec- 
tion of  a  host  of  beautiful  animals.  A  large  number 
of  our  birds  are  not  found  in  countries  where  trees 
do  not  abound.  Our  squirrels  and  various  other 
mammals  depend  upon  the  forests  for  their  main- 
tenance. Thus  the  woods  maintain  a  wider  range 
of  animals  than  can  possibly  exist  in  countries 
wThere  there  are  no  forests. 


172  PARASITIC    PLANTS. 


XIV. 

PARASITIC    PLANTS. 

TRUE  parasites  are  plants  which  attach  them- 
selves to  others  and  feed,  either  wholly  or  in  part, 
upon  stolen  juices. 

Bacteria  are  microscopic  parasites  which  mul- 
tiply with  marvellous  rapidity,  building  up  cell 
after  cell  at  the  expense  of  the  organism  in  which 
they  live.  Our  contagious  diseases  are  ascribed  to 
the  presence  of  bacteria  in  the  blood. 

Many  fungi  and  lichens  are  parasitic,  drawing 
their  nourishment  from  the  plants  on  which  they 
grow.  The  gardener  scrapes  his  fruit  trees,  that 
the  fungi  on  the  bark  may  not  extract  the  food 
which  should  all  be  used  to  nourish  blossom  and 
fruit. 

We  will  now  consider  only  the  parasites  which 
are  found  among  the  higher  plants. 

(Parasitic  ;plants  may  be  either  colored  or  green. 
The  former  class  have  no  green  leaves.  They 
are  therefore  unable  to  digest  their  own  food,  and 
must  take  it  ready-made  from  others.  The  Dodder 


PARASITIC    PLANTS.  173 

is  an  example  of  this  kind  of  parasite.  It  has  no 
roots  or  leaves,  but  lives  by  sending  suckers  into 
its  foster-plant,  or  host-plant,  and  absorbing  its 
sap. 

Green  parasites  are  able  to  elaborate  their  own 
food,  and  may  therefore  be  either  wholly  or  par- 
tially parasitic.  An  example  of  a  parasite  which 
has  no  connection  with  the  ground  is  the  English 
Mistletoe.  As  it  has  green  leaves  it  can  take  its 
raw  material  from  the  host-plant  and  make  it  into 
food,  so  that  it  probably  lives  both  on  the  crude 
sap  and  food  materials  of  the  plant  on  which  it 
grows. 

Partially  parasitic  plants  live  apparently  in  the 
usual  way,  by  the  fruits  of  their  own  labor,  and 
steal  secretly  from  the  prepared  stores  of  others. 
Our  Gerardias  are  of  this  class.  Their  roots  make 
an  underground  connection  with  the  roots  of  other 
plants  and  draw  food  from  them. 

We  will  now  examine  some  examples  of  these 
classes  a  little  more  in  detail. 

The  Dodder  is  one  of  our  most  common  para- 
sites. Its  yellow,  thread-like  stems  wind  about 
low  bushes  and  bear  clusters  of  white  flowers,  but 
they  do  not  possess  any  trace  of  leaves.  This 
plant  is  not  especially  troublesome  with  us,  but  its 


174  PARASITIC    PLANTS. 

near  relatives  in  Europe  attack  the  Flax,  Clover, 
and  Hop  fields,  and  are  much  dreaded.  The  Dod- 
der which  infests  the  Hop  is  called  in  Germany 
"Devil's  thread"  (Teufelszwirn) .  The  germina- 
tion of  our  common  species,  Cuscuta  Gronovii  is 
similar,  excepting  that  the  embryo  is  more  coiled 
in  the  seed. 

"  Among  the  species  of  Cuscuta,  certain  Euro- 
pean ones  have  obtained  a  specially  bad  reputation, 
because  they  are  so  troublesome  in  agriculture. 
The  most  notorious  of  these  is  Cuscuta  trifolii, 
called  Clover-silk  (Kleeseide),  whose  advent  in  the 
clover  fields  is  so  displeasing  to  the  farmer,  and 
whose  destruction  gives  him  so  much  trouble. 
Another  unwelcome  guest  is  Cuscuta  epilinum, 
which  winds  about  the  stern  of  the  Flax  and  hin- 
ders it  in  its  growth,  and  a  third,  Cuscuta  Europcea 
(Fig.  43),  often  destroys  the  Hop.  The  last  is  the 
most  widely  distributed  of  all  the  species  of  Cus- 
cuta, and  is  found  from  England,  through  Central 
Asia,  to  Japan,  and  southward  as  far  as  Algeria. 
It  is  not  only  parasitic  on  the  Hop,  but  also  on 
the  Elder  and  many  other  shrubs,  and  it  especially 
prefers  the  Nettle. 

"The  seeds  of  this,  as  well  as  almost  all  the 
species  of  Cuscuta,  germinate  on  damp  earth,  on 


PARASITIC    PLANTS.  175 

leaf -mould,  or  upon  the  decayed  bark  of  old  tree- 
trunks.  The  embryo,  which  lies  embedded  in  the 
albumen  of  the  one-celled  seed,  is  in  the  form  of  a 
thread  and  rolled  spirally.  It  forms  a  circle  of 
a  single  turn  or  a  turn  and  a  half,  and  is  thickened 


FIG.   43.     CUSCUTA    EUROP/EA,    PARASITIC    ON    THE    HOP.     (Natural  Size.) 
("  Pflanzenleben.") 

at  one  end  in  the  shape  of  a  club.     There  is  not  a 
trace  of  cotyledons  in  the  true  species  of  Cuscuta. 

"  The  seed  lies  on  the  ground  in  the  open  air  all 
through  the  winter,  and  germinates  very  late  in 
the  following  spring,  at  least  a  month  later  than 
the  other  seeds  .which  have  reached  the  same  spot 


176  PARASITIC    PLANTS. 

of  ground.  This  fact  is  of  great  importance  to 
the  parasite,  because  when  it  germinates  peren- 
nial plants  have  already  sent  up  stems  from  their 
underground  rootstocks.  If  the  seed  had  germi- 
nated early  in  spring,  it  would  not  easily  have 
found  a  support  in  its  immediate  neighborhood, 
while  later,  the  stem  of  an  annual,  or  the  sprout  of 
a  perennial  plant,  is  seldom  wanting  about  which 
it  can  wind. 

"  In  germination  the  spirally  rolled  embryo 
stretches  itself,  makes  a  turn  to  the  left,  takes  the 
form  of  a  bow,  and  pushes  out  its  club-shaped  end 
from  the  seed-coats  (Fig.  45,  a  to/).  This  enters 
the  ground  and  there  clings  to  withered  leaves,  etc. 
The  small  end  of  the  filiform  embryo,  still  sur- 
rounded by  the  seed-coats  and  the  albumen,  raises 
itself  in  the  opposite  direction.  Further  growth 
does  not  take  place  at  either  end,  but  in  the  middle 
of  the  thread,  and  is  very  rapid,  so  that  on  the 
fifth  day  the  whole  seedling  has  lengthened  itself 
fourfold.  On  the  third  day  of  germination  the 
seed-coats,  covering  the  upper  end,  are  thrown  off, 
and  the  apex  of  the  seedling  is  exposed.  The  store 
of  food  provided  for  the  young  plant  for  its  journey 
is  now  used  up,  and  it  is  thrown  entirely  on  its 
own  resources.  As  it  has  no  trace  of  breathing- 


PARASITIC    PLANTS.  177 

pores  it  cannot  supply  itself  with  nourishment 
from  the  air,  nor  can  it  absorb  water  with  its 
club-shaped  end.  It  grows  without  doubt  at  the 
expense  of  the  materials  which  are  contained  in 
this  thickened  end,  which  then  begins  to  shrink 
and  soon  dies  away,  while  the  upper  end  of  the 
thread  lengthens  perceptibly.  In  the  meantime, 
if  this  part  of  the  seedling  comes  in  contact 
with  anything  that  would  serve  it  as  a  support, 
it  embraces  it,  and  its  future  is  generally  as- 
sured. 

"  If  the  seedling  finds  no  support,  it  falls  upon 
the  ground  after  the  withering  of  the  club-shaped 
end;  in  this  act  it  often  strikes  a  neighboring 
plant,  and  twines  itself  immediately  about  it.  If, 
however,  a  support  is  wanting  and  the  young  seed- 
ling lies  on  the  bare  earth,  its  future  growth  is 
stopped.  It  keeps  alive  a  wonderfully  long  time, 
and  may  remain  unchanged  for  four  or  five  weeks, 
waiting  for  rescue.  Often  the  relief  comes  when 
another  plant  germinates  at  its  sides,  or  a  growing 
sprout  pushes  up  beside  it  and  touches  the  Cuscuta. 
In  this  case  it  seizes  the  friendly  cable  and  twines 
about  it.  If  no  support  is  forthcoming,  the  seed- 
ling dies.  It  is  worthy  of  notice  that  these  threads 
which  develop  suckers  when  they  are  fastened  to  a 


178  PARASITIC    PLANTS. 

living  plant,  are  unable  to  develop  any  such  absorb- 
ing organs  in  the  damp  earth. 

"  If  the  filiform  Cuscuta  seedling  grasps  a  support, 
either  while  it  still  possesses  its  club-shaped  lower 
end,  or  after  this  has  withered  away,  it  makes  two 
or  three  turns  about  its  prop,  and  then  raises  again 
its  growing  apex,  which  circles  around  like  the  hand 
of  a  clock.  By  this  movement,  which  makes  the 
impression  on  the  beholder  that  the  plant  is  grop- 
ing for  a  support,  the  thread  comes  in  contact  with 
new  stalks,  branches,  and  leaf-stems  of  other  plants, 
seizes  them,  and  makes  again  two  or  three  close 
turns  about  the  new  support.  In  this  way  the 
growing  apex  of  the  young  plant  dispenses  as  soon 
as  possible  with  dead  supports,  and  gives  the  pref- 
erence in  a  remarkable  manner  to  the  living  por- 
tions of  the  plants  on  which  it  has  fastened. 

"  When  the  Cuscuta  has  embraced  its  support, 
the  thread  swells  somewhat  and  forms  suckers, 
which  are  generally  near  together  in  a  row  of 
three,  four,  or  five  (Fig.  43). 

"  Such  a  piece  of  stem,  furnished  with  suckers, 
resembles  a  little  worm,  which  creeps  around  the 
supporting  stem.  At  first  these  suckers  are  exactly 
like  forming  roots  and  appear  smooth  on  the  upper 
surface,  but  they  soon  assume  a  finely  granular 


PARASITIC    PLANTS.  179 

appearance,  by  the  walls  of  the  epidermal  cells 
arching  outward.  By  the  help  of  these  papillae, 
and  especially  by  means  of  a  juice  which  they 
secrete,  the  suckers  fasten  themselves  to  their 
support.  If  the  suckers  have  attached  themselves 
to  a  dead  body  they  flatten  themselves  out  upon  it, 


FIG.  44.     CROSS   SECTION    OF   CUSCUTA,   PARASITIC   ON   THE   HOP. 
("  Pflanzenleben.") 

and  make  a  kind  of  disk,  which  undergoes  no  fur- 
ther development  and  serves  only  as  an  organ  of 
attachment;  but  if  the  prop  is  a  living  plant,  a 
bundle  of  cells  presses  forth  from  the  middle  of  the 
sucker,  and  presses  into  the  living  tissue  of  the 
assailed  plant  (Fig.  44).  This  entrance  is  effected 
with  great  violence.  The  bundle  of  cells  breaks 
through  the  firmly  united  cells  of  the  epidermis 


180  PARASITIC    PLANTS. 

of  the  host-plant,  often  through  a  thick  rind,  and 
penetrates  as  far  even  as  the  woody  tissue.  Once 
having  entered  the  host-plant,  the  cells,  until  now 
united  in  a  bundle,  isolate  themselves,  move  apart, 
force  themselves  singly  into  the  cells  of  the  host, 
and  become  now  active  absorbing  cells.  They 
draw  out  the  organic  substances  of  the  foster-plant 
and  bring  them  by  the  shortest  road  to  the  fibres, 
which,  in  the  meantime,  have  developed  in  the 
stem  of  the  Cuscuta,  and  are  grouped  in  a  narrow 
circle  there.  When  such  a  connection  is  finally 
established,  between  the  parasite  and  the  host- 
plant,  the  lower  portion  of  the  parasite  dies  away. 
The  club-shaped  end  has  already  disappeared,  and 
the  Cuscuta  is  now  no  longer  connected  with  the 
earth  in  which  it  has  germinated,  but  is  rooted 
only  to  the  host-plant,  by  means  of  the  suckers." 

Another  kind  of  parasite  which  is  without  green 
coloring  matter,  and  therefore  unable  to  digest  its 
own  food,  is  Beech-drops  (Epiphegus  Virginiana). 
This  is  an  example  of  a  root-parasite.  It  belongs 
to  a  family  (Orobancliacece)  consisting  of  brownish 
or  yellowish  plants,  with  scales  instead  of  leaves, 
which  are  all  root-parasites.  The  Epiphegus  lives 

1  This  account  of  the  germination  of  Dodder  is  quoted  from  "Pflan- 
zenleben,"  p.  159. 


PARASITIC    PLANTS.  181 

on  the  roots  of  the  Beech.  It  has  a  seed  without 
cotyledons  or  distinction  of  root  and  stem.  The 
seedling  is  a  thread  which  grows  downwards  till 
it  comes  in  contact  with  a  root  on  which  it  fastens. 
It  is  unable  to  take  its  food  from  the  soil.  Fig. 
45,  g  to  m,  represents  the  seedling  of  a  Broom- 
rape  (Orobanche  epithymum),  a  European  member 
of  this  family.  When  the  seedling  fastens  on  the 
root  it  thickens  and  becomes  knotty  and  warty. 
In  England  there  are  eight  species  of  Broom-rapes, 
which  grow  on  the  roots  of  Broom,  Clover,  Hemp, 
etc.  They  injure  the  clover  fields  by  stealing  the 
nourishment  from  the  roots  of  the  plants. 

There  are  a  great  many  of  these  brown,  yellow, 
or  flesh-colored  parasites  in  tropical  countries.  The 
largest  flower  in  the  world  is  said  to  belong  to  a 
parasitic  plant,  Eafflesia  Arnoldi.  It  is  a  yard 
across.  It  lives  in  Sumatra  on  the  roots  of  a  kind 
of  vine. 

The  English  Mistletoe  is  a  good  example  of  a 
wholly  parasitic  plant.  The  bright  white  berries 
are  very  attractive  to  birds,  who  eat  them  freely. 
The  hard  seeds  are  not  digested  by  the  birds  and 
fall  on  the  trees,  where  they  soon  germinate  if  the 
situation  suits  them.  They  are  especially  fond  of 
the  Black  Poplar  (Populus  nigra).  The  occurrence 


182 


PARASITIC    PLANTS. 


5  I 

J3  C 

O  « 

o  £ 


PARASITIC    PLANTS.  183 

of  the  Mistletoe  on  the  Oak  is  extremely  rare,  so 
that  it  is  said  to  have  been  regarded  by  the  Druids 
as  a  sacred  event,  and  to  have  formed  part  of  their 
religious  rites. 

The  seedling  has  two  cotyledons  which  are 
imbedded  in  albumen.  In  germination  the  por- 
tion of  the  caulicle  under  the  cotyledons  elongates, 
and  grows  towards  the  bark  of  the  tree,  exactly  as 
the  caulicle  of  an  ordinary  seedling  grows  towards 
the  ground.  When  it  reaches  the  bark  it  makes 
a  disk,  and,  out  of  the  middle  of  this  disk,  a  fine 
root-fibre  enters  the  bark  of  the  tree,  and  pene- 
trates it  as  far  as  the  wood. 

The  following  year  the  tree  forms  a  new  ring 
of  wood,  which  surrounds  the  root-fibre  of  the 
Mistletoe  and  pushes  out  the  bark  before  it.  The 
root  does  not  grow  into  the  wood,  but  the  wood 
grows  around  the  root,  so  that  it  would  in  course 
of  time  be  completely  buried  up.  To  prevent  this, 
a  zone  of  cells  is  formed  around  the  base  of  the 
Mistletoe  root,  which  keeps  pace  in  its  growth 
with  the  ring  of  wrood,  and  apparently  continues 
outward  the  growth  of  the  root.  This  growing 
zone  of  cells  sends  out  side  branches  which  run 
parallel  with  the  axis  of  the  branch  and  incorpo- 
rate themselves  with  the  bark.  These  branches 


184 


PARASITIC    PLANTS. 


develop  new  roots,  which  grow  perpendicular  to 
the  axis  of  the  branch,  and  become  gradually  sur- 
rounded with  wood,  exactly  as  happened  to  the 
first  root.  As  this  is  continued  every  year,  the 


FIG.   46. 

I.  Mistletoe  (Viscum  album),  Parasitic  on  the  Branch  of  a  Tree.  Cross-Section  through 
Branch  and  Parasite.  2.  Piece  of  Fir  Wood,  pierced  by  the  Root- Fibres  of  the  Mistle- 
toe. ("  Pflanzenleben.") 

branch  becomes  pierced  with  many  roots,  sur- 
rounded with  yearly  rings  of  wood,  which  decrease 
in  number  in  proportion  as  the  distance  from  the 
original  root  increases  (Fig.  46,  1). 

As  the  Mistletoe  has  green  leaves,  it  can  digest 


PARASITIC    PLANTS. 


185 


o      3? 
«     1 

8     iE 


186  PARASITIC    PLANTS. 

its  own  food,  and  is  not  dependent  on  the  organ- 
ized sap  of  its  host-plant. 

Finally,  there  are  many  partially  parasitic  green 
plants.  We  should  not  know  from  their  appear- 
ance that  they  were  living  on  stolen  stores.  The 
Gerardias,  Cow-wheat  (Melampyrum),  and  Yellow- 
rattle  (Rliinanthus)  are  examples  of  this  class. 
The  parasitic  habit  is  not  visible  in  these  plants  in 
the  first  stage  of  their  development.  Fig.  45,  n  to 
2),  on  p.  182,  shows  the  germination  of  a  seedling 
of  a  European  species  of  Cow-wheat  (Melampyrum 
sylvaticum).  The  seedling  throws  out  a  main  root 
an  inch  and  a  half  long  in  the  first  week,  from 
which  half  a  dozen  side  roots  branch,  without 
being  attached  to  any  other  plant.  When  these 
side  branches  have  grown  long  enough  to  come 
in  contact  with  the  roots  of  other  plants,  they 
fasten  upon  them,  develop  suckers,  and  steal  their 
juices. 

There  are  other  plants,  like  Indian  Pipe,  which 
live  on  decaying  matter  in  the  soil.  These  are 
called  Saprophytes. 

There  is  a  great  deal  still  to  be  investigated 
about  these  parasitic  plants,  and  any  good  observer 
could  record  many  interesting  facts. 


INSECTIVOROUS    TLANTSo  187 

XV. 

INSECTIVOROUS    PLANTS.1 

MARY  TREAT. 

THERE  are  many  seemingly  strange  things  in 
nature,  but  perhaps  none  more  remarkable  than 
the  fact  that  some  plants  kill  and  consume  small 
animals,  thus  reversing  the  order  of  nature's  laws, 
or  as  we  have  been  taught  to  look  upon  her  laws. 

The  most  common  of  these  plants  are  the  Sun- 
dews or  Droseras.  There  is  scarcely  a  swamp  in 
any  part  of  our  country,  either  North  or  South, 
which  does  not  contain  one  or  more  species  of 
these  interesting  plants.  The  leaves  of  the  dif- 
ferent species  are  covered  with  hair-like  glands  or, 
more  properly,  tentacles  surmounted  with  glands, 
which  exude  a  clear,  viscid  fluid  that  glistens  in 
the  sunshine  like  tiny  drops  of  dew,  from  which 
the  plants  take  the  name  of  Sundew. 

The  Eound-leaved  Sundew  (Drosera  rotundifolia) 
is  more  often  found  in  the  Northern  States  than 

1  The  first  experiments  on  the  digestion  of  animal  substances  by 
plants  were  made  by  Kanby  on  Dionaea  (1865)  and  by  Mrs.  Treat  on 
Drosera  (1871).  In  1875,  Darwin  published  "  Insectivorous  Plants." 


188  INSECTIVOROUS    PLANTS, 

either  of  the  other  species.  Its  leaves  are  ar- 
ranged in  a  rosette  and  lie  flat  on  the  ground,  or 
on  the  moss  among  which  they  often  grow.  Some 
of  these  little  plants  have  a  rosy,  pink  hue,  and 
look  wonderfully  attractive  as  they  sparkle  in  the 
sunshine.  No  doubt  the  glistening  brightness 
lures  many  little  thirsty  insects  to  the  cool-look- 
ing, dewy  leaves.  But  no  sooner  does  one  touch 
a  leaf  than  it  finds  itself  held  by  the  deceptive, 
sticky  fluid,  and  the  more  it  struggles  to  become 
free,  the  more  it  is  entangled.  As  it  stretches  and 
reaches  out  to  get  away,  it  only  comes  more  and 
more  in  contact  with  other  bristling  filaments, 
until  finally  it  has  no  power  to  move,  and  the  re- 
maining filaments  which  it  did  not  reach  are  all 
soon  curved  and  bent  toward  the  poor  captive, 
which  is  quickly  bathed  in  the  slimy  secretion, 
and  dies  within  ten  or  twenty  minutes  after  it  is 
caught.  This  secretion  dissolves  or  digests  all 
the  soft  parts  of  the  little  victim  which  are  ab- 
sorbed by  the  plant,  while  the  shelly,  indigestible 
parts  remain  on  the  leaf  until  it  becomes  dry, 
when  the  particles  are  blown  off.  As  soon  as  the 
insect  is  disposed  of,  the  tentacles  resume  their 
erect  position  and  the  glands  again  begin  to  se- 
crete the  sticky  dew  in  readiness  for  more  prey. 


INSECTIVOROUS    PLANTS. 


189 


The  illustration  of  the  Sundew  (Fig.  48)  repre- 
sents two  leaves  magnified  about  three  times. 
One  leaf  has  all  the  tentacles  in  the  normal  posi- 
tion, while  the  other  has  a  part  bent  over  some 
small  creature. 

Why  Drosera  consumes  insects  is  easier  asked 


FIG.  48,     LEAVES    OF   SUNDEW    (Drosera).     (Magnified). 

than  answered.  The  plants  live  in  water,  or  in 
very  moist  places,  where  the  roots  can  imbibe  or 
drink  so  as  to  supply  the  viscid  secretion  that  it 
may  capture  its  prey.  And  this  Round-leaved  Sun- 
dew grows  mostly  among  sphagnum  moss  where 
it  is  almost  impossible  for  it  to  obtain  the  usual 
plant-food  or  nitrogenous  matter  except  as  it  gets 


190  INSECTIVOROUS    PLANTS. 

it  from  the  insects  which  it  entraps  and  consumes. 
But  this  cannot  be  said  of  the  Long-leaved  Sundew 
(D.  longifolid)  which  grows  in  black,  muddy  ponds 
and  bogs. 

The  latter  sometimes  grows  in  water  from  ten 
to  twelve  inches  in  depth,  and  the  roots  are  im- 
bedded in  the  black  mud  beneath.  But  the  caudex, 
or  rhizoma,  is  prolonged  so  that  the  leaves  and 
flowers  are  above  the  water.  And  very  beautiful 
they  look  when  they  stand  thickly  on  the  water 
as  they  sometimes  do.  Other  water-plants  grow 
in  the  same  shallow  pond  with  this  Sundew. 
Water-lilies  —  both  Nymphcea  and  Nupliar  —  and 
the  Water-shield  (Brasenia  peltata),  and  the  pretty 
little  Floating-heart  (Limnanthemum  lacunosum), 
all  of  which  require  an  abundance  of  nitrogenous 
food,  and  would  not  grow  in  the  pond  unless  they 
could  obtain  it.  And  yet  this  Long-leaved  Sun- 
dew which  grows  with  them  is  a  most  expert 
fly-catcher,  and,  although  it  cannot  be  said  that  it 
is  necessary  for  this  plant  to  capture  insects  for 
food,  it  entraps  them  all  the  same.  Sometimes 
large  flies  and  small  butterflies  and  moths  are 
caught  and  the  leaves  roll  entirely  around  them. 
They  roll  from  the  apex  to  the  base,  holding  their 
prey  until  all  the  soft  parts  are  absorbed,  when 


INSECTIVOROUS    PLANTS.  191 

they  unfold  and  let  the  wings  and  legs  and  other 
indigestible  portions  fall  off. 

But  the  most  beautiful  and  curious  species  is 
the  Thread-leaved  Sundew  (D.  filiformis).  Its 
leaves  are  erect,  and  from  six  to  twelve  inches  in 
length  —  simply  thread-like  and  covered  with  ten- 
tacles and  glands  from  base  to  tip.  It  grows  from 
a  little  bulb  usually  in  pure  white  sand  in  springy 
places  so  that  the  sand  is  gently  overflowed  with 
water.  I  do  not  know  of  any  other  plant  more 
attractive  than  this.  It  looks  so  fresh  and  clean 
and  sparkling  in  the  pure  sand  and  water.  The 
viscid  dew  makes  it  look  as  if  covered  with  little 
gems  of  various  hues.  The  flower-scape  is  a  trifle 
longer  than  the  leaves,  and  bears  charming  rose- 
purple  flowers  an  inch  or  more  across. 

Hosts  of  insects  are  lured  by  the  brightness  of 
the  plants,  which  they  no  sooner  touch  than  they 
are  held  captive.  And  here  we  can  see  that  it 
looks  as  if  the  plants  needed  them  for  food,  grow- 
ing as  they  do  in  sand  and  water.  This  species 
kills  and  consumes  much  larger  insects  than  either 
of  the  others.  Great  dragon-flies,  butterflies,  and 
moths,  as  well  as  two-winged  flies,  are  caught  and 
killed. 

The  long  leaves,  standing  erect  and  thickly  to- 


192  INSECTIVOROUS    PLANTS. 

gether,  hold  and  bind  the  victims  much  more 
effectually  than  the  other  species.  The  larger 
the  insect  the  more  leaves  it  reaches  and  draws 
around  itself,  until  it  is  soon  bathed  in  the  sticky 
secretion  which  closes  the  trachea  or  air-tubes, 
when  it  speedily  dies. 

Like  the  other  species,  it  absorbs  the  nutritious 
parts  and  lets  the  rest  fall  at  the  base  of  the 
plant,  where  we  can  find  a  good  share  of  the  re- 
mains of  the  prey  it  has  slaughtered,  especially  of 
the  larger  insects.  Probably  this  debris  is  some- 
thing of  a  fertilizer  and  helps  to  nourish  the  plant. 

I  have  observed  two  additional  species  of  Sun- 
dew in  Florida :  D.  capillaris,  which  grows  in 
boggy  ponds,  and  bears  pale,  rose-colored  flowers, 
and  D.  brevifolia,  --a  pretty  little  plant  with 
rather  large  white  flowers,  —  found  in  the  damp 
Pine-barrens.  Both  of  these  plants  have  the  same 
fly-catching  habits.  There  is  still  another  species, 
the  Slender  Sundew  (D.  linearis),  with  which  I  am 
not  familiar.  This  grows  about  the  shores  of 
Lake  Superior.  These  are  all  of  the  Sundews,  so 
far  as  I  know,  in  our  country. 

The  Venus' s  Flytrap  (Dioncea  muscipula)  is  one 
of  the  most  singular  and  wonderful  plants  in  the 
world.  It  belongs  to  the  Sundew  family.  But, 


INSECTIVOROUS    PLANTS. 


193 


while  quite  different  from  these  plants,  it  is  more 
nearly  related  to  them  than  to  any  others,  so  that 
botanists,  not  knowing  what  else  to  do  with*  it, 


FIG.  49.     VENUS'S    FLYTRAP    (Dionaea  muscipula).     ("  Pflanzenleben.") 

have  placed  it  here.  It  is  found  only  in  the  east- 
ern part  of  North  Carolina  and  in  the  adjacent 
parts  of  South  Carolina.  It  grows  in  sandy  bogs 
in  the  low  Pine-barrens.  The  illustration  (Fig.  49), 


194  INSECTIVOROUS    PLANTS. 

although  reduced  in  size,  shows  how  singular  it 
is.  The  curious  leaves  are  all  at  the  base  of  the 
plant  close  to  the  ground.  The  flower-scape  arises 
from  the  centre,  is  about  a  foot  in  height,  and 
bears  from  eight  to  ten  pretty  white  flowers. 


FIG.  50. 

I.  Outspread   Leaf  of  Venus's  Flytrap.      2.  Section  through  a  Closed   Leaf. 
("  Pflanzenleben.") 

This  novel  Flytrap  has  no  sticky  secretion,  like 
the  Sundews,  with  which  to  capture  prey,  but  in- 
stead of  this  its  leaves  are  converted  into  traps 
something  like  a  steel  trap.  The  midrib  or  central 
vein,  which  is  thick  and  strong,  divides  the  leaf 
into  two  lobes,  each  of  which  is  furnished  with  three 
very  sensitive,  short  hairs  or  filaments,  as  may  be 
seen  in  the  illustration  of  the  single  leaf  (Fig.  50). 


INSECTIVOROUS    PLANTS.  195 

If  either  of  these  filaments  is  touched,  the  two 
lobes  fly  together  instantly,  and  the  stout  bristles 
on  the  edge  of  the  leaf  interlock  after  the  fashion 
of  a  steel  trap. 

Now  when  an  unwary  insect  alights  on  a  leaf- 
trap,  which  nature  has  set,  it  is  sure  to  touch  one 
or  more  of  the  sensitive  filaments  and  is  caught, 
and  unless  it  is  large  and  strong  it  cannot  escape. 
Strong  beetles  and  the  stronger  flies  will  force 
their  way  out  between  the  bristles,  but  the  weaker 
ones  are  held  as  if  in  a  vice,  and  are  soon  envel- 
oped in  a  slimy  secretion,  which  at  once  begins  to 
exude  from  the  inner  surface  of  the  trap,  and  after 
several  days  digests  all  of  the  soft  parts,  when  the 
leaf  slowly  opens,  and,  if  it  is  still  healthy,  is  now 
ready  for  another  victim. 

In  my  experiments,  I  have  found  that  the  Sun- 
dews digest  their  prey  more  quickly  than  the 
Dioncea.  But  I  have  worked  with  only  culti- 
vated plants ;  it  may  be  different  with  those 
growing  in  their  native  bogs,  which  I  hope  some 
of  my  young  readers  may  be  able  to  investi- 
gate. 

The  Pitcher-plant  (Sarracenia  purpurea)  (Fig. 
51)  is  another  remarkable  Flytrap  quite  common 
in  bogs  from  New  England  to  Florida.  It  is  a 


196 


INSECTIVOROUS    PLANTS. 


handsome  plant ;  both  its  leaf  and  flower  are  curi- 
ous and  beautiful. 

On  large  plants  the  leaves  are  from  six  to  eight 


FIG.  51.     PITCHER-PLANT    (Sarracenia  purpurea).     ("  Pflanzenleben.") 

inches  in  length,  and  the  flower-scape  is  a  foot  or 
more  in  height,  bearing  at  the  top  a  single,  large, 
dark,  purple  flower.  The  singular  fiddle-shaped 


INSECTIVOROUS   PLANTS.  197 

petals  are  arched  over  the  expanded  umbrella- 
shaped  style  in  a  strange  manner.  The  leaves 
grow  in  the  form  of  fanciful  pitchers,  and  hold 
water  and  usually  many  drowned  insects. 

I  have  observed  this  species  closely,  but  have 
never  been  able  to  find  what  it  is  that  attracts  so 
many  insects  into  the  pitchers.  I  am  satisfied, 
however,  from  repeated  experiments,  that  there  is 
something.  I  have  large,  strong  plants  growing 
in  an  artificial  bog  near  the  house,  where  I  can 
conduct  experiments  at  my  leisure.  When  the 
new  leaves  have  fully  expanded,  I  set  bottles 
(which  have  about  the  same  breadth  of  mouth  as 
the  leaves,  and  will  hold  about  the  same  amount) 
partly  filled  with  clear  water  by  the  side  of  some 
of  the  plants,  and  these  bottles  do  not  capture 
any  insects.  Other  bottles  of  the  same  capacity, 
partly  filled  with  sweetened  water  and  set  near 
the  leaves,  invariably  captured  as  many  insects  as 
the  leaf-pitchers,  and  yet  I  could  not  detect  any 
luring  bait  about  these  leaves ;  but  the  insects 
must  find  something  or  they  would  not  enter  into 
them  any  more  than  they  would  into  the  bottles 
of  clear  water. 

There  is  a  Pitcher-plant  (S.  variolaris)  which 
grows  in  the  South,  that  has  a  tempting  bait  ex- 


198  INSECTIVOROUS    PLANTS. 

tending  from  the  base  of  the  leaf  to  the  top,  and 
this  is  another  reason  I  have  for  thinking  that 
our  Northern  species  must  have  some  similar  con- 
trivance —  but  in  a  lesser  degree  —  to  lure  insects 
into  its  cups. 

The  leaves  of  this  Southern  species  are  straight 
tubes,  somewhat  trumpet-shaped,  standing  erect, 
and  are  from  twelve  to  fifteen  inches  in  length. 
A  hood  or  arch  covers  the  top  so  that  it  is  almost 
impossible  for  water  to  enter  them.  The  flowers 
are  yellow,  but  shaped  like  our  purple  ones.  It 
captures  great  numbers  of  insects,  which  are  at- 
tracted by  the  sweet,  sugary  secretion  which  ex- 
tends along  the  entire  length  of  the  leaf  and 
around  the  upper  edge  of  the  opening  or  mouth 
of  the  tube.  As  far  as  I  have  observed,  the  in- 
sects which  partake  of  this  secretion  always  go 
inside  of  the  tube  or  pitcher  and  never  return. 

There  is  a  difference  of  opinion  among  observers 
with  regard  to  the  action  of  the  sweet  secretion  on 
the  insects  which  partake  of  it.  I  have  given  my 
observations  and  experiments  quite  fully  in  "Home 
Studies  in  Nature,"  1  and  have  no  reason  to  modify 
in  the  least  my  views  as  therein  stated. 

1  "  Home  Studies  in  Nature/'  By  Mary  Treat.  Harper  &  Brothers. 
1871. 


INSECTIVOROUS    PLANTS.  199 

And  here  is  a  good  field  for  the  young  observer 
to  make  careful  experiments,  in  order  to  settle 
the  question  with  regard  to  the  action  of  this 
secretion  on  the  various  insects  which  feed  on  it, 
and  to  determine  why  they  do  not  get  out  of  the 
pitchers. 


BOOK  I.  40  cts.  introd.  BOOK  II.  60  cts.  introd. 

TARBELL'S 

LESSONS  IN  LANGUAGE. 

By  H,  S,  TARBELL,  Superintendent  of  Schools,  Providence,  RJ, 

Here  is  at  last  a  series  that  harmonizes  "language  "  and  "grammar"  and 
makes  expression  through  -written  forms  as  natural  as  thought  and  speech. 

It  is  believed  that  nothing  crude,  notional,  or  simply  "  taking  "  will  be 
found  in  the  books,  however  original  and  attractive  they  may  seem.  Five 
years  were  spent  in  maturing  the  plan,  and  five  years  more  in  working  out 
the  details.  The  most  approved  text-books  —  American,  English,  French, 
and  German  —  were  studied.  A  number  of  the  best  known  specialists  in 
this  department  assisted.  The  experience  of  hundreds  of  teachers  and  the 
capacity  of  thousands  of  pupils  were  consulted. 

A  course  in  which  so  much  good  thought  has  been  embodied  must  possess 
marked  features  worthy  of  attention.  The  appeal  is  confidently  made  to  the 
class-room.  All  are  urged  to  test  our  recommendations  by  actual  use. 

Win.  E.  Buck,  Supt.  Public  Instruction,  Manchester,  N.H. :  I  am  particularly  well 
pleased  with  them.  They  insure  better  teaching,  because  most  teachers  will  almost  literally 
follow  the  text-book  and  Tarbell's  Lessons  have  evidently  been  arranged  with  this  fact  in 
view.  Accordingly,  all  subjects  are  treated  with  sufficient  fullness  for  the  common  school 
and  in  due  proportion  with  reference  to  theory  and  practice. 

A.  Wanner,  City  Supt.  of  Schools,  York,  Pa.  :  They  are  admirably  adapted  to  teach 
the  pupil  "  to  use  his  native  tongue  with  readiness,  clearness  and  accuracy  in  both  its  spoken 
and  written  forms." 

Mary  A.  Bacon,  Teacher  of  English,  Girls'  Normal  and  Industrial  School,  Milledge- 
ville,  Ga. :  I  have  no  hesitation  in  saying  that  they  are  the  best  books  on  the  subject  now  in 
the  field.  The  most  inexperienced  teacher  could  not  fail  of  fair  success  with  such  texts. 

R.  W.  Stevenson,  Supt.  of  Schools,  Wichita,  Kansas :  It  will,  by  the  force  of  merit, 
push  itself  into  many  of  our  best  schools.  Teachers  will  find  it  one  of  the  best  arranged  and 
the  best  graded  of  the  many  books  on  language  culture  for  primary  schools.  The  exercises 
for  composition  are  fresh  and  pointed,  and  if  followed  must  result  in  making  the  pupil  able 
to  write  his  thoughts  accurately,  correctly  and  clearly. 

N.  Somerville,  Supt.  of  Public  Schools,  Denison,  Texas:  Tarbell's  Lessons  in  Language 
have  been  in  use  in  the  public  schools  of  this  city  five  months,  and  I  have  had  an  excellent 
opportunity  of  testing  their  efficiency  by  actual  experiment  in  the  school  room.  .  .  .  On  the 
whole  it  may  be  said  that  they  are  without  a  rival,  so  far  as  merit  is  concerned. 

George  S.  Albee,  Pres.  State  Normal  School,  Oshkosh,  Wis. :  It  constitutes  the  best 
basis  for  a  child's  progress  in  culture  in  language  known  to  me.  Its  lessons  are  not  merely 
consistent  and  progressive,  which  could  be  said  of  several  other  elementary  texts  in 
language,  but  in  addition,  they  constitute  a  linguistic  center,  which  calls  for  exercise  upon 
the  child's  varied  field  of  knowledge. 

CINN  &  COMPANY,  PUBLISHERS, 

Boston,  New  York,  and  Chicago. 


STICKNEY'S  READERS. 

Introductory  to  Classics  for  Children.  By  J.  H.  STICKNEY,  author  of 
The  Child's  Book  of  Language,  Letters  and  Lessons  in  Language^ 
English  Grammar,  etc.  Introduction  Prices:  First  Reader,  24  cents; 
Second  Reader,  32  cents  ;  Third  Reader,  40  cents  ;  Fourth  Reader, 
50  cents;  Fifth  Reader,  60  cents;  Auxiliary  Books :  Stickney  &  Pea- 
body's  First  Weeks  at  School,  1 2  cents  ;  Stickney's  Classic  Primer,  20 
cents. 

THESE  books  are,  first  of  all,  readers.  This  main  purpose, 
is  not  sacrificed  in  order  to  get  in  all  sorts  of  "  features  "  to 
entrap  the  unwary. 

The  vitality  of  methods  and  selections  preserves  the  chil- 
dren's natural  vivacity  of  thought  and  expression. 

The  editor  aimed  at  positive  excellence,  and  not  simply  to 
make  a  series  so  characterless  that  no  one,  however  unreason- 
able or  ill-informed,  could  discover  a  feature  definite  enough 
to  find  fault  with. 

This  is  almost  the  only  series  that  contains  a  sufficient 
quantity  of  reading  matter,  and  there  is  no  padding. 

Good  reading  would  not  be  good  if  it  did  not  appeal  to 
what  is  good  in  us,  and  the  lessons  in  Stickney's  Readers, 
without  "  moralizing,"  carry  moral  influence  in  warp  and  woof. 

Give  the  children  a  chance  at  these  Readers.  They  are 
the  ones  most  interested.  Ought  we  not  to  consult  their 
tastes,  which  mean  their  capacities  ?  Their  verdict  is  always 
for  Stickney. 

When  it  is  a  question  of  obstacles,  wings  are  sometimes 
worth  more  than  feet.  Stickney's  Readers  are  inspiring, 
and  lift  the  children  over  difficulties. 

Best  in  idea  and  plan  ;  best  in  matter  and  make  ;  best  in 
interest  and  results. 

They  have  found  favor  with  our  teachers  and  pupils  from  the  first. 
To  me  the  books  seem  to  be  just  what  the  gifted  author  intended  them 
to  be,  as  natural  and  beautiful  as  childhood  itself.  They  deserve  the 
greatest  success.  — A.  R.  Sabin,  Assistant  Supt.,  Chicago,  III. 


CINN  &  COMPANY,  Publishers, 

Boston,  New  York,  and  Chicago, 


OPEN  SESAME! 

About  One  Thousand  Pieces  of  the  Choicest  Prose  and  Verse. 

COMPILED  BY 
BLANCHE  WILDER  BELLAMY  AND  MAUD  WILDER  GOODWIN. 

VOL.  I.  for  children  from  four  to  ten  years  old. 
VOL.  II.  for  children  from  ten  to  fourteen  years  old. 
VOL.  III.  for  children  of  a  larger  growth. 

Illustrated,  and  handsomely  bound  in  cloth.     Price  of  each  to 
teachers,  and  for  introduction,  75  cents. 


No  Eastern  romancer  ever  dreamed  of  such  a  treasure- 
house  as  our  English  literature. 

With  this  "  Open  Sesame  "  in  his  possession  a  boy  or  girl 
has  only  to  enter  and  make  its  wealth  his  own. 

Every  piece  is  believed  to  be  worth  carrying  away  in  the 
memory. 

The  best  writings  of  our  classic  authors  are  here,  with 
selections  from  recent  literature  and  not  a  few  translations. 

It  is  very  good  indeed.  We  think  it  the  best  of  all  the  collections.  —  E.  A. 
SHELDON,  Prin.  State  Normal  School,  Os-wego,  N.  Y. 

I  think  it  by  far  the  best  collection  of  memory  pieces  I  have  ever  seen.  —  F.  B. 
PALMER,  Prin.  State  Normal  School,  Fredonia,  N.  Y. 

It  is  a  beauty,  and  of  all  similar  works  I  have  seen,  it  has  the  most  desirable 
selections.  —  W.  E.  BUCK,  Supt.  Public  Schools,  Manchester,  N.  H. 

The  book  is  a  handsome  specimen  of  the  arts  of  typography  and  binding, 
while  the  selections  and  their  arrangement  speak  well  for  the  judgment  and  taste 
of  the  editors.—  C HAS.  W.  COLE,  Supt.  Public  Schools,  Albany,  N.  Y. 

It  [Volume  I.]  is  a  rare  and  rich  collection  of  poems  and  a  few  prose 
articles.  —  INTER-OCEAN,  Chicago. 

The  whole  book  is  full  to  overflowing  of  the  best  things  to  be  found  in  the 
English  language,  and  is  a  thoroughly  happy  production  which  children,  parents, 
and  teachers  will  welcome  eagerly. —  EDUCATION,  Boston. 

It  is  not  often  that  a  collection  of  verse  so  thoroughly  representative,  of  what 
is  best  in  literature,  and  so  inclusive  of  what  one  has  learned  to  love  and  to  look 
for  in  every  anthology,  comes  from  the  press.  —  CHRISTIAN  UNION,  New  York. 

The  editors  have  brought  to  their  task  a  sufficiently  wide  and  sympathetic 
knowledge  of  English  and  American  verse,  and  have  also  wisely  considered  the 
real  needs  and  tastes  of  children.  .  .  .  The  collection  is  at  once  of  a  high  char- 
acter and  of  a  practicable  sort. —  SUNDAY  SCHOOL  TIMES,  Philadelphia. 


CINN  &  COMPANY,  Publishers, 

Boston,  New  York,  Chicago,  and  London. 


THE  NATIONAL  MUSIC  COURSE 

Aims 

To  place  vocal  music  on  the  same  footing  as  the  regular  school  studies,  and 
enable  the  class  teachers  to  give  successful  instruction  in  music,  as  in  geog- 
raphy and  arithmetic,  under  competent  direction. 

IT  HAS  srcci:i:i>i:i> 

Fully,  as  the  list  of  places  using  it  proves.  The  testimony  of  teachers,, 
superintendents,  and  musicians  is  unmistakable  evidence  of  its  excellence 
and  superiority. 

"  If  there  is  any  argument  in  pure  merit,  the  National  should  head  the  list  of  music 
courses.  . . .  Very  rarely  is  as  much  genius,  study,  and  research  devoted  to  the  prepara- 
tion of  a  series  of  books  as  has  been  given  by  Professor  Mason  to  the  National  Course. 
The  books  stand  the  severest  tests  of  time  and  use." — T.  E.  HAZELL,  Special  Teacher 
tf  Music,  New  York  City. 


MORE 

THAN 

ANY 

OTHER 


endorsed  by  wide  use  and  satisfactory  results. 
approved  by  musical  authorities  here  and  abroad, 
recommended  on  a  careful  examination  of  its  merits, 
enjoyed  by  the  teachers  who  teach  and  the  children  who  study  it* 


SOME  POINTS  OF  EXCELLENCE, 
x.  It  is  based  on  the  fundamental  principles  of  education. 

2.  It  combines  the  best  musical  theory  with  the  best  methods  of  teaching,  analogous 
to  those  followed  in  other  branches  of  school  study,  particularly  the  teaching  of  language. 

3.  The  instruction  is  comprehensive  and  thorough,  systematically  and  progressively 
developed  from  the  lowest  grades  to  the  highest,  and  fitted  to  the  school-room  and  the 
usual  course  of  study. 

4.  The  best  composers  are  represented,  and  the.  best  song-writers. 

5.  The  music  is  taking  and  interesting  to  children;  it  wears  well,  and  does  not  grow 
stale. 

6.  The  literature  is  appropriate,  dignified,  and  improving. 

7.  It  presents  the  fruit  of  the  best  musical  study  and  experience  in  all  countries. 
&    It  is  endorsed  by  long  and  wide  use,  in  America  and  in  foreign  countries. 

g,    It  is  endorsed  by  practical  teachers  of  school  music,  by  superintendents,  by  clasi 
teachers,  and  by  musical  experts. 

10.  Those  who  have  most  thoroughly  studied  the  System  are  most  firmly  convinced  ol 
its  excellence  and  its  superiority. 

11.  Thoroughly  tested  under  most  varied   conditions,  it  is  beyond  the  period  oi 
experiment. 

12.  It  is  fresh  and  abreast  of  the  times,  and  will  always  be  kept  in  line  with  the  newest 
approved  thought. 

13.  It  exerts  a  strong  influence  toward  the  good  order  of  the  school  and  the  refinement 
of  the  pupils. 

14.  It  not  only  appeals  to  the  musical  children,  but  awakens  and  develops  the  un 
musical. 

15.  It  requires  but  little  time,  is  not  expensive,  and  can  certainly  be  handle**  by  th» 
regular  teachers  under  proper  supervision. 

16.  Properly  taught,  it  is  sure  to  produce  the  desired  result. 


GINN  &  COMPANY,  PUBLISHERS, 
BOSTON,  NEW  YORK,  AND  CHICAGO. 


Musical  Publications. 


Tnfrrwl 

Caswell  &  Ryan :  Time  and  Tune  Series.  Price. 

Book  I.     The  ^Eolian $0.65 

Book  II.     Ths  Barcarolle 94 

Coda Supplementary  Music  for  Public  Schools.     No. 

200  now  ready.     Send  for  List. 

Eichberg Girls'  High  School  Music  Reader 1.25 

New  High  School  Music  Reader 94 

High  School  Music  Reader  (old  edition) 94 

Eichberg  &  Sharland:  Fourth  Music  Reader  (Revised) 94 

Abridged  Fourth  Music  Reader  (Revised)  75 

Emerson,  Brown  &  Gay:  The  Morning  Hour 50 

Leib Voices  of  Children 40 

Mason New  First  Reader 25 

New  Second  Reader 40 

New  Third  Reader 40 

Independent  Reader 70 

Abridged  Independent  Reader 60 

National  Music  Teacher 40 

Hymn  and  Tune  Book  for  Female  Voices 60 

Hymn  and  Tune  Book  for  Mixed  Voices 60 

Independent  and   Hymn  and   Tune   Book  for 

Mixed  Voices  (combined) 94 

New  First,  Second,  and  Third  Series  of  Music 

Charts each  9.00 

Time-Name  Chart 75 

Transposition  Chart 75 

Mason  &  Veazie :  New  Fourth  Music  Reader 90 

National  Music  Course.     See  Mason,  Mason  &  Veazie,  Eichberg, 
Eichberg  &  Sharland. 

Pease Singing-Book 70 

Russell ..Chromatic  Chart 2.00 

Tilden Common  School  Song  Reader 36 

Common  School  Chart 5.00 

Handbook  of  First-Year  Lessons 10 

Veazie School  Singer oo 

Music  Primer 05 

Four-Part  Song  Reader 40 

Young Institute  Song  Collection 10 

Zuchtmann  &  Kirtland :  Choral  Book....  ,    .60 


GINN  &  COMPANY,  Publishers, 

BOSTON,  NEW  YORK,  AND  CHICAGO. 


NATURAL  SCIENCE. 


Elements  of  Physics. 


A  Text-book  for  High  Schools  and  Academies.  By  ALFRED  P.  GAGE, 
A.M.,  Instructor  in  Physics  in  the  English  High  School,  Boston.  12mo. 
424  pages.  Mailing  Price,  $1.25;  Introduction,  $1.12. 


HPHIS  treatise  is  based  upon  the  doctrine  of  the  conservation  of 
energy,  which  is  made  prominent  throughout  the  work.  But 
the  leading  feature  of  the  book  —  one  that  distinguishes  it  from 
all  others  —  is,  that  it  is  strictly  experiment-teaching  in  its  method ; 
i.e.,  it  leads  the  pupil  to  "read  nature  in  the  language  of  experi- 
ment." So  far  as  practicable,  the  following  plan  is  adopted  :  The 
pupil  is  expected  to  accept  as  fact  only  that  which  he  has  seen  or 
learned  by  personal  investigation.  He  himself  performs  the  larger 
portion  of  the  experiments  with  simple  and  inexpensive  apparatus, 
such  as,  in  a  majority  of  cases,  is  in  his  power  to  construct  with  the 
aid  of  directions  given  in  the  book.  The  experiments  given  are 
rather  of  the  nature  of  questions  than  of  illustrations,  and  precede 
the  statements  of  principles  and  laws.  Definitions  and  laws  are  not 
given  until  the  pupil  has  acquired  a  knowledge  of  his  subject  suffi- 
cient to  enable  him  to  construct  them  for  himself.  The  aim  of  the 
book  is  to  lead  the  pupil  to  observe  and  to  think. 


Wm.  Noetling,  State  Normal 
School,  Bloomsburg,  Pa. :  I  know  of 
no  other  work  on  the  subject  that 
I  can  so  unreservedly  recommend  to 
all  wide-awake  teachers  as  this. 

Benj.  F.  Thomas,  Prof,  of  Physics, 
Ohio  State  University :  I  have  used 
it  with  preparatory  classes  for  sev- 
eral years  with  satisfaction.  I  re- 
gard it  as  the  best  for  class-room 
work. 


H.   Wilson    Harding,    Prof,    of 

Physics,  Lehigh  University :  I  be- 
lieve Gage's  Elements  of  Physics  to 
be  based  on  the  true  method  of  study- 
ing that  branch  of  science,  —  that  of 
practical  work  in  the  laboratory  by 
the  student  himself. 

C.  F.  Emerson,  Prof,  of  Physics, 
Dartmouth  College :  It  takes  up  the 
subject  on  the  right  plan,  and  pre- 
sents it  in  a  clear  yet  scientific  way. 


100  NATURAL   SCIENCE. 

Introduction  to  Physical  Science. 

By  A.  P.  GAGE,  Instructor  in  Physics  in  the  English  High  School,  Bos- 
ton,  Mass.,  and  author  of  Elements  of  Physics,  etc.  12mp.  Cloth. 
viii  +  353  pages.  With  a  color  chart  of  spectra,  etc.  Mailing  price, 
$  1.10;  for  introduction,  $1.00. 

rpHE   constantly  increasing  popularity   of   Gage's  Elements  of 

'  Physics  has  created  a  demand  for  an  easier  book,  on  the  same 
plan,  suited  to  schools  that  can  give  but  a  limited  time  to  the 
study.  The  Introduction  to  Physical  Science  meets  this  demand. 

In  a  text-book,  the  first  essentials  are  correctness  and  accuracy. 
It  is  believed  that  the  Introduction  will  stand  the  closest  expert 
scrutiny.  Especial  care  has  been  taken  to  restrict  the  use  of  scien- 
tific terms,  such  as  force,  energy,  power,  etc.,  to  their  proper  signifi- 
cations. Terms  like  sound,  light,  color,  etc.,  which  have  commonly 
been  applied  to  both  the  effect  and  the  agent  producing  the  effect, 
have  been  rescued  from  this  ambiguity. 

Recent  advances  in  physics  have  been  faithfully  recorded,  and 
the  relative  practical  importance  of  the  various  topics  has  been 
taken  into  account.  Among  the  new  features  are  a  full  treatment 
of  electric  lighting,  and  descriptions  of  storage  batteries,  methods 
of  transmitting  electric  energy,  simple  and  easy  methods  of  mak- 
ing electrical  measurements  with  inexpensive  apparatus,  the  com- 
pound steam-engine,  etc.  Static  electricity,  now  generally  regarded 
as  of  comparatively  little  practical  importance,  is  treated  briefly; 
while  dynamic  electricity,  the  most  promising  physical  agent  of 
modern  times,  is  placed  in  the  clearest  light  of  our  present 
knowledge. 

The  wide  use  of  the  Elements  under  the  most  varied  conditions, 
and,  in  particular,  the  author's  own  experience  in  teaching  it,  have 
shown  how  to  improve  where  improvement  was  possible.  The 
style  will  be  found  suited  to  the  grades  that  will  use  the  book. 
The  experiments  are  of  practical  significance,  and  simple  in  manip- 
ulation. ^The  Introduction  is  even  more  fully  illustrated  than  the 
Elements. 

The  Introduction,  like  the  author's  Elements,  has  this  distinct 
and  distinctive  aim,  —  to  elucidate  science,  instead  of  "  populariz- 
ing" it;  to  make  it  liked  for  its  own  sake,  rather  than  for  its  gild- 


NATURAL   SCIENCE. 


101 


ing  and  coating;  and,  while  teaching  the  facts,  to  impart  the  spirit 
of  science,  that  is  to  say,  the  spirit  of  our  civilization  and  progress. 


Alexander  Macfarlane,  Prof,  of 
Physics,  University  of  Texas :  I  con- 
sider that  the  principal  features  of 
the  book —  its  clearness  and  accuracy 
of  statement,  its  information  being 
up  to  date,  and  the  practical  nature 
of  the  instruction  —  make  it  valua- 
ble as  a  first  text-book  in  Physics  in 
high  schools  and  academies,  and  es- 
pecially for  those  institutions  that 
prepare  for  the  universities. 

I.  Thornton  Osmond,  Prof,  of 
Physics,  State  College,  Pa. :  For 
selection  of  matter  and  method  of 
treatment,  for  comprehensiveness, 
brevity,  clearness,  and  accuracy,  for 
the  simplicity  and  value  of  experi- 
ments, it  was,  and  yet  is,  unrivalled 
as  a  text-book  for  high  school  and 
academic  work. 

George  E.  Gay,  Prin.  of  High 
School,  Maiden,  Mass. :  With  the 
matter,  both  the  topics  and  their  pre- 
sentation, I  am  better  pleased  than 
with  any  other  Physics  I  have  seen. 

J.  P.  Naylor,  Prof,  of  Physics,  De 
Pauw  University;  In  its  scientific 


spirit,  and  in  accuracy  and  clearness 
of  statements  of  principles,  I  know 
nothing  that  is  its  superior.  The  ex- 
tent to  which  the  work  is  carried  is 
also  about  what  can  be  well  done  in 
the  time  our  schools  usually  have  to 
give  to  the  subject.  It  is  used  in 
preparatory  work  at  this  University 
as  the  best  we  can  get. 

0.  C.  Kinyon,  Teacher  of  Physics 
in  High  School,  Syracuse,  N.  Y. :  It 
not  only  insures  an  interest  in  the 
study  but  tends  to  thoroughly  arouse 
those  powers  of  observation,  the  de- 
velopment of  which  is  the  especial 
province  of  scientific  study. 

B.  C.  Hinde,  Professor  Natural 
Science,  Trinity  College,  N.  C. :  I 
have  used  Gage's  Introduction  to 
Physical  Science  for  two  years,  and 
I  consider  it  the  best  book  published 
for  its  purpose.  It  is  strictly  in 
accord  with  the  best  modern  teach- 
ing of  Physics.  I  have  made  it  a 
point  to  call  the  attention  of  my  stu- 
dents to  this  book  that  they  may  use 
it  in  their  teaching. 


Physical  Laboratory  Manual  and  Note  Booh. 

By  A.  P.  GAGE,  Instructor  in  Physics  in  English  High  School,  Boston, 
and  author  of  Elements  of  Physics,  Introduction  to  Physical  Science, 
etc.  12mo.  Boards,  xii  +  244  pages.  By  mail,  45  cents  ;  for  introduction, 
35  cents. 


manual  has  been  prepared  especially  to  accompany  the 
"  author's  text-books,  but  is  adapted  for  use  in  connection  with 
any  good  text-book  on  the  subject.  The  left-hand  page  contains 
cuts  of  apparatus  to  be  used,  directions  for  performing  experiments 
(upwards  of  one  hundred  in  number),  and  questions  to  be  an- 
swered in  connection  with  the  experiments.  Suggestions  to 
teachers,  the  needed  tables,  etc.,  are  provided  at  the  beginning. 
The  right-hand  pages  are  left  blank  for  the  pupil's  notes. 


102 


NATURAL    SCIENCE. 


A  Students'  Manual  of  a  Laboratory  Course  in 

Physical  Measurements. 

By  WALLACE  CLEMENT  SABINE,  A.M.,  Instructor  in  Harvard  Univer- 
sity. 8vo.  Cloth,  ix+126  pages.  Mailing  price,  $1.35;  for  intro- 
duction, $1.25. 


manual,  which  is  intended  for  use  in  supplementing  col- 
lege courses  in  physics,  contains  an  outline  of  seventy  experi- 
ments in  mechanics,  sound,  heat,  light,  magnetism  and  electricity, 
arranged  with  special  regard  to  a  systematic  and  progressive  de- 
velopment of  the  subject.  The  description  of  each  experiment  is 
accompanied  by  a  brief  statement  of  the  physical  principles  and 
definitions  involved,  and  a  proof  of  necessary  formulae. 


Le  Koy  C.  Cooley,  Professor  of 
Physics,  Vassar  College :  I  have  ex- 
amined it  and  am  ready  to  com- 
mend it. 

Fernando  Sanford,  Professor  of 
Physics,  Leland  Stanford  Junior 
University:  I  like  the  book  very 


much.  It  is  better  adapted  to  the 
kind  of  work  which  I  am  trying  to 
do  than  any  other  book  I  have  seen. 
J.  F.  Woodhull,  Professor  of  Sci- 
ence, Teachers'  College,  New  York: 
I  find  Sabiue's  Laboratory  Manual 
a  thoroughly  good  thing. 


High  School  Laboratory  Manual  of  Physics. 

By  DUDLEY  G.  HAYS,  CHARLES  D.  LOWRY,  and  AUSTIN  C.  RISHEL, 
Teachers  of  Physics  in  the  Chicago  High  Schools.  8vo.  Cloth. 
iv  +  154  pages.  Mailing  price,  00  cents;  for  introduction,  50  cents. 


manual  has  been  written:   First,  to  present  a  logically 
arranged   course  of   experimental  work  covering  the  ground 
of  Elementary  Physics.     Second,  to  provide  sufficient  laboratory 
work  to  meet  college  entrance  requirements.     It  contains  equiva- 
lents of  most  of  the  exercises  in  the  Harvard  Pamphlet. 

The  experiments  are  largely  quantitative,  but  qualitative  work 
is  introduced.  Apparatus  has  been  chosen  that  may  in  most 
cases  be  duplicated  at  small  cost.  Special  care  has  been  taken  to 
make  details  of  work  clear,  and  to  instruct  the  pupil  in  the 
methods  of  making  generalizations  from  his  results.  Alternate 
pages  are  blank  for  convenience  in  taking  notes. 


W.  S.  Jackman,  Teacher  of  Science, 
Cook  Co.  Normal  School,  Englewood, 
III. :  It  is  a  most  excellent  manual 


and  I  believe  it  meets  the  needs  of 
high  schools  on  this  subject  better 
than  any  other  book  I  have  seen. 


NATURAL    SCIENCE. 


103 


Introduction  to  Chemical  Science. 

By  R.  P.  WILLIAMS,  Instructor  in  Chemistry  in  the  English  High 
School,  Boston.  12mo.  Cloth.  216  pages.  By  mail,  90  cents;  for 
introduction,  80  cents. 

fTlHIS  work  is  strictly,  but  easily,  inductive.  The  pupil  is  stimu- 
lated by  query  and  suggestion  to  observe  important  phenomena, 
and  to  draw  correct  conclusions.  The  experiments  are  illustrative, 
the  apparatus  is  simple  and  easily  made.  Such  elements,  com- 
pounds, and  experiments  as  pupils  have  no  use  for,  are  omitted. 
The  nomenclature,  symbols,  and  writing  of  equations  are  made 
prominent  features.  In  descriptive  and  theoretical  chemistry,  the 
arrangement  of  subjects  is  believed  to  be  especially  superior  in 
that  it  presents,  not  a  mere  aggregation  of  facts,  but  the  science 
of  chemistry.  Brevity  and  concentration,  induction,  clearness, 
accuracy,  and  a  legitimate  regard  for  interest,  are  leading  charac- 
teristics. The  treatment  is  full  enough  for  any  high  school  or 
academy. 

Though  the  method  is 'an  advanced  one,  it  has  been  so  simplified 
that  pupils  experience  no  difficulty,  but  rather  an  added  interest, 
in  following  it ;  the  author  himself  has  successfully  employed  it  in 
classes  so  large  that  the  simplest  and  most  practical  plan  has  been 
a  necessity. 


H.  T.  Fuller,  Pres.  of  Polytechnic 
Institute,  Worcester,  Mass.:  It  is 
clear,  concise,  and  suggests  the  most 
important  and  most  significant  ex- 
periments for  illustration  of  general 
principles. 

Thos.  C.  Van  Nuys,  Prof,  of  Chem- 
istry, Indiana  University,  Bloom- 
ington,  Ind.:  I  consider  it  an  excel- 
lent work  for  students  entering  upon 
the  study  of  chemistry. 

0.  W.  Shaw,  Prof,  of  Chemistry, 
Pacific  University, Forest  Grove,0r.: 
I  am  especially  pleased  with  it  as 
filling  a  place  which  no  other  work 
has  filled. 


W.  J.  Martin,  Prof,  of  Chemistry, 
Davidson  College,  N.C. :  I  think  it 
is  one  of  the  most  admirable  little 
text-books  I  have  ever  seen. 

Wm.  F.  Langworthy,  Teacher  of 
Chemistry,  Colgate  Academy,  Hamil- 
ton, JV.  Y. :  I  am  much  pleased  that 
we  introduced  it. 

T.  H.  Norton,  Prof,  of  Chemistry, 
Cincinnati  University,  0. :  Its  clear- 
ness, accuracy,  and  compact  form 
render  it  exceptionally  well  adapted 
for  use  in  high  and  preparatory 
schools.  I  shall  warmly  recommend 
it  for  use  whenever  the  effort  is  made 
to  provide  satisfactory  training  in 


104 


NATURAL   SCIENCE. 


accordance  with  the  requirements  for 
admission  to  the  scientific  courses  of 
the  University. 

C.  F.  Adams,  Teacher  of  Science, 
High  School,  Detroit,  Mich. :  I  have 
carried  two  classes  through  Wil- 
liam's Chemistry,  and  the  book  has 
surpassed  my  highest  expectations. 
It  gives  greater  satisfaction  with 
each  succeeding  class. 

C.  K.  Wells,  formerly  Supt.  of 
Schools,  Marietta,  0. :  The  book 
bears  acquaintance  the  best  of  any 
book  of  like  character  that  I  have 
ever  examined. 

W.  T.  Mather,  Teacher  of  Science, 
Williston  Seminary,  Fasthampton, 
Mass. :  I  have  used  the  book  in  the 
laboratory  very  successfully.  I  can 
heartily  commend  it  for  the  method 
used  and  the  clear  and  concise  treat- 
ment of  the  subject. 

J.  W.  Simmons,  Supt.  Schools, 
Owosso,  Mich. :  The  proof  of  the 
merits  of  a  text-book  is  found  in  the 
crucible  of  the  class-room  work. 


There  are  many  chemistries,  and 
good  ones;  but,  for  our  use,  this 
leads  them  all.  There  is  enough  and 
not  too  much  in  the  work.  It  is 
stated  in  language  plain,  interesting 
and  not  misleading.  A  logical  order 
is  followed,  and  the  mind  of  the 
student  is  at  work  because  of  the 
many  suggestions  offered.  Our  high 
schools  have  no  province  in  chemistry 
beyond  the  basic  facts.  Too  many 
text-books  go  beyond  this  introduc- 
tory field,  but  not  far  enough  to  clear 
away  the  mists  that  arise.  The  stu- 
dent's mind  is  lumbered  with  things 
of  which  he  sees  no  application.  It 
is  not  education  but  the  barest  kind 
of  stuffing. 

We  use  Williams's  work  and  the 
results  are  all  we  could  wish.  There 
is  plenty  of  chemistry  in  the  work 
for  any  of  our  high  schools.  The 
above  opinion  is  based  upon  an  ex- 
perience of  twelve  years  as  teacher 
of  chemical  science. 


Laboratory  Manual  of  General  Chemistry. 

By  R.  P.  WILLIAMS,  Instructor  in  Chemistry,  English  High  School,  Bos- 
ton, and  author  of  Introduction  to  Chemical  Science.  12mo.  Boards, 
xvi  +  200  pages.  By  mail,  30  cents ;  for  introduction,  25  cents. 

rpHE  book  contains  one  hundred  experiments  in  general  chemistry 
and  qualitative  analysis,  blanks  opposite  each  for  pupils  to 
take  notes,  laboratory  rules,  complete  tables  of  symbols,  with 
chemical  and  common  names,  reagents,  solutions,  chemicals,  and 
apparatus,  and  the  plan  of  a  model  laboratory.  Minute  directions, 
and  suggestions  designed  to  help  the  pupils  observe  and  draw 
inferences,  characterize  each  experiment. 


W.  M.  Stine,  Prof,  of  Chemistry, 
Ohio  University,  Athens,  0. :  It  is  a 
work  that  has  my  heartiest  endorse- 
ment. I  consider  it  thoroughly  peda- 


gogical in  its  principles,  and  Its  use 
must  certainly  give  the  student  the 
greatest  benefit  from  his  chemical 
drill. 


108 


NATURAL   SCIENCE. 


Scheiner's  Astronomical  Spectroscopy. 

Department  of  Special  Publication.  —  Translated,  revised  and  en- 
larged by  E.  B.  FROST,  Associate  Professor  of  Astronomy  in  Dart- 
mouth College.  8vo.  Half  leather.  Illustrated,  xiii  +  482  +  pages. 
Price  by  mail,  $5.00  ;  for  introduction,  $4.75. 

HP  HIS  work  aims  to  explain   the   most   practical   and   modern 
methods  of  research,  and  to  state  our  present  knowledge  of 
the  constitution,  physical  condition  and  motions  of  the  heavenly 
bodies,  as  revealed  by  the  spectroscope. 

There  are  three  parts  :  —  I.  Spectroscopic  Apparatus  ;  II.  Spec- 
tral Theories  ;  III.  Results  of  Spectroscopic  Observations,  with  a 
fourth  containing  tables  of  wave-lengths  of  lines  of  the  solar 
spectrum,  catalogues  of  stars  with  special  types  of  spectra,  and  a 
full  bibliography  brought  down  to  1893.  Some  matter  has  been 
added  and  some  changes  made  in  the  translation  to  adapt  it  more 
nearly  to  English  and  American  readers.  Rowland's  system  of 
wave-lengths  is  thoroughly  brought  down  to  date. 

Elements  of  Structural  and  Systematic  Botany. 

For  High  Schools  and  Elementary  College  Courses.  By  DOUGLAS 
HOUGHTON  CAMPBELL,  Ph.D.,  Professor  of  Botany  in  the  Leland  Stan- 
ford Junior  University.  12mo.  Cloth,  ix  +  253  pages.  Price  by 
mail,  $1.25;  for  introduction,  $1.12. 

rpHE  fundamental  peculiarity  and  merit  of  this  book  is  that  it 
begins  with  the  simple  forms,  and  follows  the  order  of  nature 
to  the  complex  ones.     Tradition  has  been  discarded  throughout, 
and  the  most  recent  and  reliable  authorities  are  followed. 


K.  Ellsworth  Call,  Teacher  of 
Natural  Science,  High  School,  West 
Des  Moines,  la. :  It  is  the  only 
manual  which  combines  just  enough 

Plant  Organization. 


technic  with  a  logical  treatment  of 
the  more  minute  structure  of  plants 
to  render  it  a  help  to  the  teacher  of 
to-day. 


tion,  75  cents. 
TT  consists  of  a  synoptical  review  of  the  general  structure  and 

morphology  of  plants,  with  blanks  for  written  exercises  by 
pupils. 


NATURAL    SCIENCE.  109 

Blaisdell's  Physiologies. 

By  ALBERT  F.  BLAISDELL,  M.D. 
The  Child's  Book  of  Health. 

Ke vised  Edition.  In  easy  lessons  for  schools.  Illustrated.  Mailing 
price,  35  cents;  for  introduction,  30  cents. 

How  to  Keep  Well. 

Revised  Edition.  A  text-book  of  health  for  use  in  the  lower  grade  of 
schools.  Mailing  price,  55  cents ;  for  introduction,  45  cents. 

Our  Bodies  and  How  We  Live. 

Revised  Edition.  A  text-hook  of  physiology  and  hygiene  adapted  for 
use  in  advanced  grammar  schools  and  high  schools.  12mo.  Cloth, 
vi  +  403  pages.  Mailing  price,  75  cents ;  for  introduction,  65  cents. 

How  to  Teach  Physiology.     A  Handbook  for  Teachers.    10  cents. 

T>LAISDELL'S  PHYSIOLOGIES  are  true,  scientific,  interesting, 
and  teachable.  The  matter  is  fresh  and  to  a  considerable 
extent  new.  The  language  is  clear,  terse,  and  suggestive.  Special 
emphasis  is  laid  upon  the  personal  care  of  health.  Reference  is 
made  throughout  the  series  to  the  evil  eft'ects  of  stimulants  and 
narcotics  on  the  human  system. 

The  important  facts  in  "  How  to  Keep  Well  "  and  "  Our  Bodies  " 
are  illustrated  by  a  systematic  series  of  simple  experiments.  This 
feature  is  peculiar  to  the  Blaisdell  books  and  has  been  found  no 
less  valuable  than  original.  Endorsed  by  the  W.  C.  T.  U. 

A  Hygienic  Physiology. 

For  the  Use  of  Schools.  By  D.  F.  LINCOLN,  M.D.,  Author  of  School 
and  Industrial  Hygiene,  etc.  12mo.  Cloth.  Illustrated,  v  +  206 
pages.  Price  by  mail,  90  cents;  for  introduction,  80  cents. 

TT  is  the  distinctive  feature  of  this  book  to  put  hygiene  first  and 
make  anatomy  and  physiology  tributary,  instead  of   making 
anatomy  and  physiology  the  main  things  and  introducing  hygiene 
incidentally. 

An  Epitome  of  Anatomy,  Physiology,  and  Hy- 

giene.  —Including  the  Effects  of  Alcohol  and  Tobacco. 

By  H.  H.  CULVER,  formerly  Teacher  of  Physiology  in  Bishop  College, 
Marshall,  Texas.  8vo.  Boards.  22  pages.  By  mail,  25  cents;  for 
introduction,  20  cents.  A  concise,  tabular  view  of  the  whole  subject. 


MONTGOMERY'S 

Histories  of  England  and  France  are  said  by  all  to  be,  in 
their  departments,-  unequalled  in  scholarship,  in  true  historic 
insight  and  temper,  in  interest  and  class-room  availability. 
They  are  admittedly  the 

LEADING 

text-books  on  their  subjects.  Their  popularity  and  wide  use 
have  been  duly  proportionate  to  their  merits.  Hundreds  of 
schools  have  introduced  them,  and  all  report  the  greatest 
satisfaction.  These 

FACTS 

led  every  one  to  expect  a  great  deal  of  the  author's  History 
of  the  United  States.  No  one  has  been  disappointed.  The 
attractive  and  enduring  qualities  of  the  other  books  are  here 
found  in  even  higher  degree.  Not  the  least 

OF 

these  are  the  numberless  incidental  touches  of  thought,  fact, 
or  feeling  that  illuminate  the  narrative,  and  both  stimulate 
and  satisfy  the  reader's  interest,  —  one  result  of  the  author's 
mastery  of  his  subject.  As  one  would  infer,  the  author  is 
thoroughly 

AMERICAN 

in  his  sympathies  and  feelings,  —  too  American,  in  fact,  to 
be  sectarian,  partisan,  local,  or  narrow,  —  and  so  we  find 
remarkable  life  and  breadth,  as  well  as  insight  and  instruc- 
tion, in  this  book.  What  we  have  is,  in  short,  a 

HISTORY 

of  the  American  people,  of  its  development  in  all  depart- 
ments of  activity,  with  both  the  causes  and  the  results  of 
great  movements  distinctly  traced:  a  vivid  and  attractive 
panorama  of  the  leading  facts  of  our  history. 

Introductory  Price,  $1.00 
GINN    &    COMPANY,  Publishers, 

BOSTON.  NEW  YORK,  AND  CHICAGO. 


A    REVOLUTION    IN    SCHOOL    READING 


HAS   BEEN    WROUGHT   BY   THE    USE   OF   THE 

Classics  for  Children 


The  books  in  this  carefully  edited  series  are  widely  used 
in  place  of  the  ordinary  Reading  Books  in  the  upper  grades 
of  the  Grammar  Schools  and  in  the  High  Schools.  They 
are  also  used  as  Supplementary  Readers  in  hundreds  of 
schools  throughout  the  country. 

DESIGN  — 

To  supply  material  for  practice  in  reading,  form  a  taste  for 
good  literature,  and  increase  the  mental  power  of  the  pupils  by 
providing  them  with  the  best  works  of  standard  authors,  complete 
as  far  as  possible,  and  judiciously  annotated. 

AUTHORSHIP  — 

Varied,  and  of  world-wide  reputation.  In  the  list  of  authors 
are  Shakespeare,  Ruskin,  Scott,  Irving,  Goldsmith,  Johnson, 
Franklin,  Andersen,  Kingsley,  De  Foe,  Swift,  Arnold,  and  Lamb. 

EDITORS  — 

Of  recognized  ability  and  discriminating  taste.  Among  them 
are  John  Fiske,  Edward  Everett  Hale,  Henry  N.  Hudson, 
Charlotte  M.  Yonge,  John  Tetlow,  Homer  B.  Sprague,  D.  H. 
Montgomery,  Edwin  Ginn,  W.  H.  Lambert,  Alfred  J.  Church, 
Dwight  Holbrook,  J.  H.  Stickney,  Margaret  A.  Allen,  and 
Mary  S.  Avery. 

INDORSED   BY 

Teachers,  Superintendents,  Librarians,  eminent  Literary 
Authorities,  and  the  Educational  Press. 


CLASSICS    FOR    CHILDREN. 


Choice    Literature ;    Judicious    Notes ;    Large    Type ;    Firm 
Einding ;    Low    Prices. 


Hans  Andersen's  Fairy  Tales. 

*  FIRST  SERIES:  Supplementary  to  the  Third  Reader. 

*  SECOND  SERIES:  Supplementary  to  the  Fourth  Reader. 
*/Esop  's  Fables,  with  selections  from  Krilof  and  La  Fontaine. 
*Kingsley's  Water-Babies  :  A  story  for  a  Land  Baby. 
*Ruskin  's  King  of  the  Golden  River :  A  Legend  of  Stiria. 
*The  Swiss  Family  Robinson.     Abridged. 

Robinson  Crusoe.     Concluding  with  his  departure  from  the  island. 
*Kingsley's  Greek  Heroes.    FranciUon's  Gods  and  Heroes. 

Lamb 's  Tales  from  Shakespeare.     "  Meas.  for  Meas."  omitted. 

Scott's  Tales  of  a  Grandfather. 
*Martineau's  Peasant  and  Prince. 

Bunyan's  Pilgrim's  Progress. 

Scott's  Lady  of  the  Lake.     Scott's  Lay  of  the  Last  Minstrel. 

Lamb 's  Adventures  of  Ulysses. 

Tom  Brown  at  Rugby.     Lord  Chesterfield's  Letters. 

Church 's  Stories  of  the  Old  World. 

Scott's  Talisman.     Complete. 

Scott's  Quentin  Durward.     Slightly  abridged. 

Irving 's  Sketch  Book.     Six  selections,  including  '•  Rip  Van  Winkle," 

Shakespeare's  Merchant  of  Venice. 

Scott's  Guy  Mannering.     Complete. 

Scott's  Ivanhoe.     Complete.        Scott's  Rob  Roy.     Complete. 

Johnson 's  Rasselas,  Prince  of  Abyssinia. 

Gulliver's  Travels.     The  Voyages  to  Lilliput  and  Brobdingnag. 

Plutarch 's  Lives.     From  Clough's  Translation. 

Irving-Fiske's  Washington  and  His  Country. 

Goldsmith's  Vicar  of  Wakefield. 
*Franklin:  His  Life  by  Himself. 

Selections  from  Ruskin. 
*Hale's  Arabian  Nights.     Heroic  Ballads. 

Grote  and  Segur's  Two  Great  Retreats. 

Irving's  Alhambra.    Selections  for  Memorizing. 

Scott's  M arm  ion.     Scott's  Old  Mortality. 

Don  Quixote.    Thoughts  of  Marcus  Aurelius  Antoninus.    Epictetus* 


Starred  books  are  illustrated. 


CINN    &    COMPANY,   Publishers, 

BOSTON,  NEW  YORK,  AND  CHICAGO. 


WENTWORTH'S  ARITHMETICS. 

Adopted  for  exclusive  use  in  the  state  of  Washington,  and  in 
countless  cities,  towns,  and  schools. 


MASTERY :  their  motto. 

LEARN  TO  DO  BY  DOING:  their  method. 

PRACTICAL  ARITHMETICIANS:  the  result. 


WENTWORTH'S  PRIMARY  ARITHMETIC. 

By  G.  A.  WENTWORTH,  Professor  of  Mathematics  in  Phillips 
Exeter  Academy,  and  Miss  E.  M.  Reed,  Principal  of  the  Train- 
ing School,  Springfield,  Mass.  Profusely  illustrated.  Introduc- 
tion price,  30  cents. 

In  a  word,  this  book  —  the  fruit  of  the  most  intelligent  and 
painstaking  study,  long-continued  —  is  believed  to  represent  the 
best-known  methods  of  presenting  numbers  to  primarians,  and  to 
present  these  methods  in  the  most  available  form.  It  is  com- 
mended as  profoundly  philosophical  in  method,  simple  and 
ingenious  in  development,  rich  and  varied  in  matter,  attractive 
in  style,  and  practical  in  effect. 

It  has  been  carefully  and  critically  examined  by  myself  and  my  teachers,  and  in  our 
estimation  it  stands  ahead  of  anything  else  of  the  kind  that  we  have  found.  —  PRINCIPAL 
CAMPBELL,  State  Normal  School,  Johnson,  Vt. 

WENTWORTH'S  GRAMMAR  SCHOOL  ARITHMETIC. 

Illustrated.     Introductory  price,  65  cents. 
Answers  free  on  teachers'  orders. 

Intended  to  follow  the  Primary  Arithmetic  and  make  with  that  a 
two-book  series  for  common  schools.  It  is  designed  to  give  pupils 
of  the  grammar-school  age  an  intelligent  knowledge  of  the  subject 
and  a  moderate  power  of  independent  thought,  by  training  them  to 
solve  problems  by  neat  and  intelligent  methods  and  keeping  them 
free  from  set  rules  and  formulas.  It  is  characterized  by  accuracy, 
thoroughness,  good  sense,  school-room  tact,  and  practical  ingenuity. 

Eminently  practical,  well  graded,  and  well  arranged.  ...  I  consider  it  the  brightest, 
most  attractive,  most  scholarly  text-book  on  this  subject  that  has  been  issued  for  years. 
—  PRINCIPAL  SERVISS,  Amsterdam,  N.  Y. 

In  a  word,  these  books  represent  the  Best  Methods,  made 
feasible,  with  the  Best  Problems,  —  ingenious,  varied,  practical, 
and  abundant.  

GINN    &    COMPANY,    PUBLISHERS. 

BOSTON,  NEW  YORK,  CHICAGO,  AND  LONDON. 


WENTWORTH'S  ARITHMETICS. 


Crystallized  from  years  of  study  and  experience ;  sharp  in  outline ; 
clear  in  substance.  These  books  are  characterized,  like  the  author's 
academic  text-books,  by  the  closest  adaptation  to  the  needs  of  the 
pupil  and  the  requirements  of  class-room  study.  They  economize 
time  and  mental  energy,  while  they  secure  the  most  distinct  and 
lasting  impressions.  Note  the  following  testimonials :  — 


PBIMABY  ARITHMETIC, 
Warren  Holden,  Prof.  Mathematics, 
Girard  College,  Philadelphia  :  I  think 
it  admirably  adapted  for  the  purpose 
intended. 

J.  A.  Graves,  Prin.  South  Gram- 
mar School,  Hartford,  Conn.:  I  am 
glad  to  find  at  last  a  real  Primary 
Arithmetic. 

T.  M.  Balliet,  Supt.  Schools,  Spring- 
field, Mass. :  It  is  based  on  right  prin- 
ciples, and  the  details  are  worked  out 
with  care. 

E.  C.  Branson,  Supt.  Schools,  Ath- 
ens, Ga.  :  The  best  to  date  in  America ; 
and,  in  fact,  the  only  Primary  Arith- 
metic worth  putting  into  the  hands  of 
pupils  at  all. 

J.  M.  Green,  Prin.  State  Normal  and 
Model  Schools,  New  Jersey :  It  is  a 
book  in  which  the  authors  manifest 
what  seems  to  me  to  be  the  true  un- 
derstanding of  what  constitutes  pri- 
mary work  in  number. 

S.  A.  Ellis,  Supt.  Schools,  Rochester, 
N.  Y.  :  The  methods  followed  are  ap- 
proved by  our  best  educators.  The 
examples  are  practical  and  sufficiently 
numerous ;  and,  in  fact,  nothing  seems 
to  have  been  omitted  that  would  tend 
to  give  a  young  pupil  a  clear  and  sat- 
isfactory idea  of  the  various  processes 
•in  Arithmetic. 


GRAMMAR  SCHOOL  ARITHMETIC. 

A.  B.  Fifield,  Prin.  Eaton  School, 
New  Haven,  Conn.!  It  is  a  model 
text-book. 

John  R.  Dunton,  Prin.  Grammar 
School,  Lewiston,  Me.  :  It  is  an  excel- 
lent book.  Both  its  matter  and  meth- 
ods of  treatment  are  well  adapted  to 
grammar  school  needs. 

E.  C.  Willard,  Prin.  High  School, 
Westerly,  R.I.:  Nearly  every  page 
bears  the  characteristic  marks  of  the 
author,  who  easily  leads  to-day  in 
mathematical  book-making. 

P.  T.  Bugbee,  Prin.  Union  School, 
Newark,  N.  Y.:  It  has  stood  the  test 
of  several  years  with  us,  and  I  consider 
it  superior  to  any  other  Arithmetic  of 
grammar  grade  which  I  have  seen. 

G.  S.  Albee,  Pres.  State  Normal 
School,  Oshkosh,  Wis.:  The  abun- 
dance of  concrete  problems  tending 
to  exercise  the  pupil  in  more  respects 
than  in  a  mere  process,  is  a  very  com- 
mendable feature. 

Edward  Taylor,  Supt.  Schools,  Vm- 
cennes,  Ind.:  It  is  sufficient  to  say 
that  we  have  been  using  it  as  the  sole 
pupil's  text  in  that  grade  for  five  years 
past,  and  always  with  entire  satisfac- 
tion. 


GINN  &  COMPANY,  Publishers, 

BOSTON,  NBW  YORK,  AND  CHICAGO. 


"VB  36068 


